Shop Ethernet Network Switch

Sponsored
About our ads
$525.00
Rauland Responder 5 351004 8 Port Ethernet Switch Wpoe - Pre-Owned
BEC Integrated
$525.00
Rauland Responder 5 351004 8 Port Ethernet Switch Wpoe - Pre-Owned
BEC Integrated
$59.68
TP-Link 5-Port Gigabit Ethernet Poe+ Managed Switch, 1000Mbps, Black (TL-SG105PE)
Staples
1K+
$59.68
TP-Link 5-Port Gigabit Ethernet Poe+ Managed Switch, 1000Mbps, Black (TL-SG105PE)
Staples
1K+
$199.99
NETGEAR 16-Port Poe+ Gigabit Ethernet Unmanaged Essentials Switch (GS316PP) - With 16 X Poe+ @ 183W, Desktop Or Wall Mount
Amazon.com
228
Free shipping
$199.99
NETGEAR 16-Port Poe+ Gigabit Ethernet Unmanaged Essentials Switch (GS316PP) - With 16 X Poe+ @ 183W, Desktop Or Wall Mount
Amazon.com
228
$985.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Non Latching
L-com Global Connectivity
$985.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Non Latching
L-com Global Connectivity
$93.00
Mini Industrial 5 Ports Gigabit Poe Switch Hardened 5 Port RJ45 10/100/1000Mbps 802.3At Ethernet Switch Din Rail Mount Poe+ Switch (-40 To 167 ºF)
Amazon.com
51
Free shipping
$93.00
Mini Industrial 5 Ports Gigabit Poe Switch Hardened 5 Port RJ45 10/100/1000Mbps 802.3At Ethernet Switch Din Rail Mount Poe+ Switch (-40 To 167 ºF)
Amazon.com
51
$249.99
NETGEAR 48-Port Gigabit Ethernet Unmanaged Essentials Switch (GS348) - Desktop Or Rackmount, Silent Operation
Amazon.com
172
Free shipping
$249.99
NETGEAR 48-Port Gigabit Ethernet Unmanaged Essentials Switch (GS348) - Desktop Or Rackmount, Silent Operation
Amazon.com
172
$182.93
2891002 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFNB 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$182.93
2891002 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFNB 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$266.63
2891518 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFN 7GT/SX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$266.63
2891518 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFN 7GT/SX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$82.06
Cisco CBS110 5T D Unmanaged Switch 5 Port Gigabit Ethernet Desktop
4TEKGear.com
51
$82.06
Cisco CBS110 5T D Unmanaged Switch 5 Port Gigabit Ethernet Desktop
4TEKGear.com
51
$3.99
$13.30
Gigabit Switch 5 Ports 100/1000Mbps Network Switcher RJ45 LAN Hub Ethernet 1000Mbps Stable Smart
AliExpress
70% off
$3.99
$13.30
Gigabit Switch 5 Ports 100/1000Mbps Network Switcher RJ45 LAN Hub Ethernet 1000Mbps Stable Smart
AliExpress
$240.30
2989365 Phoenix Contact - Industrial Ethernet Switch - FL NAT SMN 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation Products
PLC Direct
$240.30
2989365 Phoenix Contact - Industrial Ethernet Switch - FL NAT SMN 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation Products
PLC Direct
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
50% off
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity
$6,411.00
Allen-Bradley 1783-CMS20DN Stratix 5200 Ethernet Switch 20-P, A
PLCHardware.com
$6,411.00
Allen-Bradley 1783-CMS20DN Stratix 5200 Ethernet Switch 20-P, A
PLCHardware.com
$231.00
Allen-Bradley 1783-BMS10CA Stratix 5700 Ethernet Switch, Ser. A
PLCHardware.com
$231.00
Allen-Bradley 1783-BMS10CA Stratix 5700 Ethernet Switch, Ser. A
PLCHardware.com
$38.08
5 Port 10/100/1000 Gigabit Ethernet Switch, Black, Energy Efficient Ethernet / IEEE 802.3Az Support
CableWholesale
$38.08
5 Port 10/100/1000 Gigabit Ethernet Switch, Black, Energy Efficient Ethernet / IEEE 802.3Az Support
CableWholesale
$290.60
8 Port 10/100/1000 Gigabit Ethernet Switch, Matte Grey
CableWholesale
$290.60
8 Port 10/100/1000 Gigabit Ethernet Switch, Matte Grey
CableWholesale
$28.51
8 Port 10/100 Fast Ethernet Switch, Magnetic Base
CableWholesale
$28.51
8 Port 10/100 Fast Ethernet Switch, Magnetic Base
CableWholesale
$27.49
Tp-Link 8-Port Gigabit Ethernet Desktop Switch, Tl-Sg108
Office Depot
3
$27.49
Tp-Link 8-Port Gigabit Ethernet Desktop Switch, Tl-Sg108
Office Depot
3
$15.29
RJ45 5/8 Port Fast Ethernet 10/100/1000Mbps High-Quality Fast Network Ethernet Data Switch Suitable
AliExpress
Free shipping
$15.29
RJ45 5/8 Port Fast Ethernet 10/100/1000Mbps High-Quality Fast Network Ethernet Data Switch Suitable
AliExpress
Free shipping
$34.99
Tp-Link 5-Port 10/100/1000Mbps Desktop Switch - 5 Ports - Gigabit Ethernet - 10/100/1000Base-T - 2 Layer Supported - Tlsg605
Office Depot
132
$34.99
Tp-Link 5-Port 10/100/1000Mbps Desktop Switch - 5 Ports - Gigabit Ethernet - 10/100/1000Base-T - 2 Layer Supported - Tlsg605
Office Depot
132
$1,019.99
HPE Networking Instant On 1960 48 Port Gigabit Smart Managed Switch
4TEKGear.com
4
$1,019.99
HPE Networking Instant On 1960 48 Port Gigabit Smart Managed Switch
4TEKGear.com
4
$999.99
Netgear AV Line M4250-8G2XF-Poe+ Switch 10-Port Gigabit Ethernet Switch With Netgear IGMP Plus, Mounting Ears, Quiet Mode, AV Web-Based GUI,
Sweetwater
$999.99
Netgear AV Line M4250-8G2XF-Poe+ Switch 10-Port Gigabit Ethernet Switch With Netgear IGMP Plus, Mounting Ears, Quiet Mode, AV Web-Based GUI,
Sweetwater
$162.74
Hikvision DS-3E0510P-E 8-Port Gigabit Unmanaged POE+ Switch
A1 Security Cameras
$162.74
Hikvision DS-3E0510P-E 8-Port Gigabit Unmanaged POE+ Switch
A1 Security Cameras
$27.99
Intellinet 8-Port Fast Ethernet Office Switch, Desktop Size, Metal, Ieee 802.3Az (Energy Efficient Ethernet), Box - Switch - 8 X 10/100 - Desktop
Office Depot
$27.99
Intellinet 8-Port Fast Ethernet Office Switch, Desktop Size, Metal, Ieee 802.3Az (Energy Efficient Ethernet), Box - Switch - 8 X 10/100 - Desktop
Office Depot
$160.00
Uswitch | Control Anything Anywhere Over The Web Or Network Relay Switch
uHaveControl
$160.00
Uswitch | Control Anything Anywhere Over The Web Or Network Relay Switch
uHaveControl
$84.99
NETGEAR Essentials GS308LP 8-Port Smart Gigabit Ethernet Switch With Poe+ Support
Crutchfield
$84.99
NETGEAR Essentials GS308LP 8-Port Smart Gigabit Ethernet Switch With Poe+ Support
Crutchfield
$299.99
Humminbird AS ETH 5PGGL 5-Port Ethernet Switch
Cabela's
29
$299.99
Humminbird AS ETH 5PGGL 5-Port Ethernet Switch
Cabela's
29
$265.00
Uswitch CS - Wifi/Ethernet Web Controlled Relays And I/O Uswitch CS Relay Switch
uHaveControl
$265.00
Uswitch CS - Wifi/Ethernet Web Controlled Relays And I/O Uswitch CS Relay Switch
uHaveControl
$79.00
Automation Direct | SE-SW5U | 5-Port Industrial Ethernet Switch |
Classic Automation
1
$79.00
Automation Direct | SE-SW5U | 5-Port Industrial Ethernet Switch |
Classic Automation
1
$0.01
Comtrend - GS-7305 - 5-Port Gigabit Ethernet Switch-Comtrend
Netceed
$0.01
Comtrend - GS-7305 - 5-Port Gigabit Ethernet Switch-Comtrend
Netceed
Types of Ethernet Cables Explained | Straight-Through, Crossover & Console Cables
0:16
Types of Ethernet Cables Explained | Straight-Through, Crossover & C…
16 views2 months ago
YouTubeNetwork Educative
FIX Ethernet Connected but No Internet Access on Windows 10
0:33
FIX Ethernet Connected but No Internet Access on Windows 10
4.2K views1 month ago
YouTubeTricknology
Ethernet Cable Types!!!!🔥🔥
0:16
Ethernet Cable Types!!!!🔥🔥
1.2K views1 month ago
YouTubeNetworkShip
Ethernet Splitter vs Switch: Which One Do You Need?
0:58
Ethernet Splitter vs Switch: Which One Do You Need?
10.6K views4 months ago
YouTubeBroadbandNow
Networking Cables Explained | Ethernet vs Fiber vs Coaxial
0:23
Networking Cables Explained | Ethernet vs Fiber vs Coaxial
411 views3 weeks ago
YouTubeGuiNet
Ethernet Cable Connected but no Internet Access FIX ( 2025 )
0:16
Ethernet Cable Connected but no Internet Access FIX ( 2025 )
864.1K views7 months ago
YouTubeEtechniz
What Is a LAN Cable? Explained for Beginners! #techhighlights #LANCable #ethernetcable
0:52
What Is a LAN Cable? Explained for Beginners! #techhighlights #LAN…
4.2K views2 months ago
YouTubeCLGD SOLUTIONZ
0:57
Use Ethernet Cables as Jumper Wires!
184.5K views6 months ago
YouTubeCore Electronics
1:15
Installing a computer socket rj 45 #electrician
39.1K views5 months ago
YouTubemontage_1_region
2:26
Restore Wi-Fi connection | HP OfficeJet Pro 8120, 8130, 9110, 91…
687 views2 months ago
YouTubeHP Support
1:34
Siemens Scalance XC 224 | Industrial ethernet switch #autom…
42 views3 weeks ago
YouTubePLC Nerd
0:52
Carterpcs on TikTok
2.9M views2 weeks ago
TikTokcarterpcs
0:20
Ethernet vs WiFi: Understanding Internet Speed Differences
5M views6 months ago
TikTokf2x_dragon
0:49
Test Wired Internet with a Flipper Zero Easily
1.3M views6 months ago
TikTokflipperzero
0:30
Understanding Ethernet Cables and Their Benefits
252.1K views4 weeks ago
TikToktamiastar
0:10
Echo Networks on TikTok
892.4K viewsApr 2, 2024
TikTokengineer._chris
5:50
Ethernet Blueprint on TikTok
144.4K viewsFeb 24, 2023
TikTokethernetblueprint
0:15
Danny and Aly on TikTok
86.5K views1 month ago
TikTokdannyandaly
0:07
Suggested accounts
65.6K views1 month ago
TikTokjumper.sienna
See more videos
Static thumbnail place holder

Shop Ethernet Network Switch

Sponsored
About our ads
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
50% off
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity
$6,411.00
Allen-Bradley 1783-CMS20DN Stratix 5200 Ethernet Switch 20-P, A
PLCHardware.com
$6,411.00
Allen-Bradley 1783-CMS20DN Stratix 5200 Ethernet Switch 20-P, A
PLCHardware.com
$231.00
Allen-Bradley 1783-BMS10CA Stratix 5700 Ethernet Switch, Ser. A
PLCHardware.com
$231.00
Allen-Bradley 1783-BMS10CA Stratix 5700 Ethernet Switch, Ser. A
PLCHardware.com
$38.08
5 Port 10/100/1000 Gigabit Ethernet Switch, Black, Energy Efficient Ethernet / IEEE 802.3Az Support
CableWholesale
$38.08
5 Port 10/100/1000 Gigabit Ethernet Switch, Black, Energy Efficient Ethernet / IEEE 802.3Az Support
CableWholesale
$290.60
8 Port 10/100/1000 Gigabit Ethernet Switch, Matte Grey
CableWholesale
$290.60
8 Port 10/100/1000 Gigabit Ethernet Switch, Matte Grey
CableWholesale
$28.51
8 Port 10/100 Fast Ethernet Switch, Magnetic Base
CableWholesale
$28.51
8 Port 10/100 Fast Ethernet Switch, Magnetic Base
CableWholesale
$27.49
Tp-Link 8-Port Gigabit Ethernet Desktop Switch, Tl-Sg108
Office Depot
3
$27.49
Tp-Link 8-Port Gigabit Ethernet Desktop Switch, Tl-Sg108
Office Depot
$15.29
RJ45 5/8 Port Fast Ethernet 10/100/1000Mbps High-Quality Fast Network Ethernet Data Switch Suitable
AliExpress
Free shipping
$15.29
RJ45 5/8 Port Fast Ethernet 10/100/1000Mbps High-Quality Fast Network Ethernet Data Switch Suitable
AliExpress
$34.99
Tp-Link 5-Port 10/100/1000Mbps Desktop Switch - 5 Ports - Gigabit Ethernet - 10/100/1000Base-T - 2 Layer Supported - Tlsg605
Office Depot
132
$34.99
Tp-Link 5-Port 10/100/1000Mbps Desktop Switch - 5 Ports - Gigabit Ethernet - 10/100/1000Base-T - 2 Layer Supported - Tlsg605
Office Depot
$1,019.99
HPE Networking Instant On 1960 48 Port Gigabit Smart Managed Switch
4TEKGear.com
4
$1,019.99
HPE Networking Instant On 1960 48 Port Gigabit Smart Managed Switch
4TEKGear.com
$999.99
Netgear AV Line M4250-8G2XF-Poe+ Switch 10-Port Gigabit Ethernet Switch With Netgear IGMP Plus, Mounting Ears, Quiet Mode, AV Web-Based GUI,
Sweetwater
$999.99
Netgear AV Line M4250-8G2XF-Poe+ Switch 10-Port Gigabit Ethernet Switch With Netgear IGMP Plus, Mounting Ears, Quiet Mode, AV Web-Based GUI,
Sweetwater
$162.74
Hikvision DS-3E0510P-E 8-Port Gigabit Unmanaged POE+ Switch
A1 Security Cameras
$162.74
Hikvision DS-3E0510P-E 8-Port Gigabit Unmanaged POE+ Switch
A1 Security Cameras

Shop Ethernet Network Switch

Sponsored
About our ads
$525.00
Rauland Responder 5 351004 8 Port Ethernet Switch Wpoe - Pre-Owned
BEC Integrated
$525.00
Rauland Responder 5 351004 8 Port Ethernet Switch Wpoe - Pre-Owned
BEC Integrated
$59.68
TP-Link 5-Port Gigabit Ethernet Poe+ Managed Switch, 1000Mbps, Black (TL-SG105PE)
Staples
1K+
$59.68
TP-Link 5-Port Gigabit Ethernet Poe+ Managed Switch, 1000Mbps, Black (TL-SG105PE)
Staples
1K+
$199.99
NETGEAR 16-Port Poe+ Gigabit Ethernet Unmanaged Essentials Switch (GS316PP) - With 16 X Poe+ @ 183W, Desktop Or Wall Mount
Amazon.com
228
Free shipping
$199.99
NETGEAR 16-Port Poe+ Gigabit Ethernet Unmanaged Essentials Switch (GS316PP) - With 16 X Poe+ @ 183W, Desktop Or Wall Mount
Amazon.com
228
$985.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Non Latching
L-com Global Connectivity
$985.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Non Latching
L-com Global Connectivity
$93.00
Mini Industrial 5 Ports Gigabit Poe Switch Hardened 5 Port RJ45 10/100/1000Mbps 802.3At Ethernet Switch Din Rail Mount Poe+ Switch (-40 To 167 ºF)
Amazon.com
51
Free shipping
$93.00
Mini Industrial 5 Ports Gigabit Poe Switch Hardened 5 Port RJ45 10/100/1000Mbps 802.3At Ethernet Switch Din Rail Mount Poe+ Switch (-40 To 167 ºF)
Amazon.com
51
$249.99
NETGEAR 48-Port Gigabit Ethernet Unmanaged Essentials Switch (GS348) - Desktop Or Rackmount, Silent Operation
Amazon.com
172
Free shipping
$249.99
NETGEAR 48-Port Gigabit Ethernet Unmanaged Essentials Switch (GS348) - Desktop Or Rackmount, Silent Operation
Amazon.com
172
$182.93
2891002 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFNB 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$182.93
2891002 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFNB 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$266.63
2891518 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFN 7GT/SX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$266.63
2891518 Phoenix Contact - Industrial Ethernet Switch - FL SWITCH SFN 7GT/SX | PLC Direct | Programmable Logic Controllers And Industrial Automation
PLC Direct
$82.06
Cisco CBS110 5T D Unmanaged Switch 5 Port Gigabit Ethernet Desktop
4TEKGear.com
51
$82.06
Cisco CBS110 5T D Unmanaged Switch 5 Port Gigabit Ethernet Desktop
4TEKGear.com
51
$3.99
$13.30
Gigabit Switch 5 Ports 100/1000Mbps Network Switcher RJ45 LAN Hub Ethernet 1000Mbps Stable Smart
AliExpress
70% off
$3.99
$13.30
Gigabit Switch 5 Ports 100/1000Mbps Network Switcher RJ45 LAN Hub Ethernet 1000Mbps Stable Smart
AliExpress
$240.30
2989365 Phoenix Contact - Industrial Ethernet Switch - FL NAT SMN 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation Products
PLC Direct
$240.30
2989365 Phoenix Contact - Industrial Ethernet Switch - FL NAT SMN 8TX | PLC Direct | Programmable Logic Controllers And Industrial Automation Products
PLC Direct
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$1,060.00
L-Com CAT6 A/B Network Switch W/ IP Ethernet Control - Latching
L-com Global Connectivity
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
50% off
$61.80
$123.60
5-Port Industrial-Grade Ethernet Metal Switch 100m Network Port Rail Installation ODOT-MS105T
AliExpress
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$119.98
NETGEAR Prosafe 24-Port 10/100 Fast Ethernet Switch JFS524
FireFold
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$2,540.24
Meraki Ms225 24P Ethernet Switch 24 Network 4 Uplink
4TEKGear.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$611.00
Allen-Bradley 1783-LMS8 Stratix 2500 Ethernet Switch, 8 Ports, A
PLCHardware.com
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$97.24
Kele | Gs105na | Netgear Switch | Network And Wireless - Switch
Kele
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity
$740.00
L-Com CAT6 A/B Network Switch - Latching
L-com Global Connectivity

  • Ethernet Switches - High-Speed Ethernet Switches

    https://www.sitime.com
    About our ads
    SponsoredSiTime offers advanced timing solutions, perfect for any high-tech application. Leadi…
    Site visitors: Over 10K in the past month

    3E DCOCXOs available · Environmental stressors · 50% lower power

    Types: 5G, Aerospace & Defense, Automotive, Industrial, Medical