What are modular connectors?
Modular connectors are commonly used for telephone systems, data networks, and low-speed serial connections. These connectors are inexpensive, relatively simple to terminate, and easy to plug and unplug. A modular connector typically has a clear, plastic body, with a tab that locks the plug and jack into place when connected. In the vernacular used by the technology industry, they are called "RJ" connectors. This is technically inaccurate, but the naming convention is widely used. RJ is an acronym for Registered Jack, which is part of a coding system developed in the 1970s by AT&T to classify telephone services and equipment. The system, called the Universal Service Order Code (USOC), used designations that began with the letters RJ to denote the capabilities of jacks in a building, and how they should be wired in order to connect to the public phone network. RJ plug connections are typically terminated by using a special tool to crimp the connector onto the conductors of a cable. These connections are often made in the field for convenience; however, a factory-assembled RJ cable typically offers the best performance.Select the modular connector that you want to learn more about:
The RJ-12 connector has 6-position, 6-conductor arranged in a single row. This connector is used for voice/data applications: telephone (two-line), networking, extended-distance peripherals.
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7ft (2.1m) RJ12 6P6C Straight Modular Cable
09598 | C2G
For RS-232 modular adapters for dumb terminal hookups and other serial/parallel extension applications.
$2.99
50ft (15.2m) RJ12 6P6C Straight Modular Cable
08115 | C2G
For RS-232 modular adapters for dumb terminal hookups and other serial/parallel extension applications.
$15.99
14ft (4.25m) RJ12 6P6C Straight Modular Cable
09600 | C2G
For RS-232 modular adapters for dumb terminal hookups and other serial/parallel extension applications.
$4.99
The wiring scheme for a single line phone was identified as "RJ11", and the name stuck to describe the connector used on a phone cord. Today, RJ-11 is widely used in the connectivity industry to denote a 6-position, 4-conductor modular connector or jack.
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7ft (2.1m) RJ11 Modular Telephone Cable
02970 | C2G
Connect your phone, modem or fax machine to the wall jack
$2.99
7ft (2.1m) RJ11 6P4C Straight Modular Cable
02971 | C2G
For RS-232 modular adapters for dumb terminal hookups and other serial/parallel extension applications.
$2.99
25ft (7.6m) RJ11 6P4C Straight Modular Cable
02973 | C2G
For RS-232 modular adapters for dumb terminal hookups and other serial/parallel extension applications.
$3.99
50ft (15.2m) RJ11 High Speed Internet Modem Cable
28724 | C2G
Connect your analog or digital (DSL/ISDN) modem to a telephone wall jack
$36.99
15ft (4.6m) RJ11 High Speed Internet Modem Cable
28722 | C2G
Connect your analog or digital (DSL/ISDN) modem to a telephone wall jack
$13.99
100ft (30.5m) RJ11 High Speed Internet Modem Cable
28726 | C2G
Connect your analog or digital (DSL/ISDN) modem to a telephone wall jack
$59.99
25ft (7.6m) RJ11 High Speed Internet Modem Cable
28723 | C2G
Connect your analog or digital (DSL/ISDN) modem to a telephone wall jack
$25.99
7ft (2.1m) RJ11 High Speed Internet Modem Cable
28721 | C2G
Connect your analog or digital (DSL/ISDN) modem to a telephone wall jack
$8.99
14ft (4.25m) RJ11 Modular Telephone Cable
09590 | C2G
Connect your phone, modem or fax machine to the wall jack
$3.99
75ft (22.8m) RJ11 Modular Telephone Cable
09594 | C2G
Connect your phone, modem or fax machine to the wall jack
$13.99
An 8-position, 8-conductor modular connector that is most often used for data networks such as Ethernet. RJ-45 connectors are physically wider than the RJ-11/12 connectors used for telephone. In network applications, RJ-45 cable assemblies are used to connect from a patch panel to a network switch, and also to connect a computer's NIC to a data port.
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1ft (0.3m) Cat5e Non-Booted Unshielded (UTP) Ethernet Network Patch Cable - Blue
25462 | C2G
For network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications.
$2.99
50ft (15.2m) Cat5e Snagless Unshielded (UTP) Ethernet Network Patch Cable - Black
20038 | C2G
Snagless design for network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications
$15.99
1ft (0.3m) Cat5e Snagless Unshielded (UTP) Ethernet Network Patch Cable - Black
26969 | C2G
Snagless design for network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications
$2.99
1ft (0.3m) Cat5e Snagless Unshielded (UTP) Ethernet Network Patch Cable - Red
26968 | C2G
Snagless design for network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications
$2.99
3ft (0.9m) Cat6 Snagless Unshielded (UTP) Network Crossover Patch Cable - Yellow
27871 | C2G
Easily transfer files and data between two computers by using this cable to connect and create a peer-to-peer network
$5.99
50ft (15.2m) Cat5e Non-Booted Unshielded (UTP) Ethernet Network Patch Cable - Blue
24393 | C2G
For network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications.
$14.99
15ft (4.6m) Cat6 Snagless Unshielded (UTP) Ethernet Network Patch Cable - Blue
22015 | C2G
Snagless design for network adapters, hubs, switches, routers, DSL/cable modems, patch panels and other high performance networking applications.
$9.99
RJ45 Network Combiner Kit
37049 | C2G
Connect two network devices over single 10/100 network cable drop to two Ethernet ports
$24.99
7ft (2.1m) Cat6 Snagless Shielded (STP) Ethernet Network Patch Cable - Yellow
00865 | C2G
Protect from EMI/RFI interference
$7.99
3ft (0.9m) Cat6 Snagless Unshielded (UTP) Slim Ethernet Network Patch Cable - Blue
01076 | C2G
Small diameter cable designed for high density, 1 Gigabit or 10 Gigabit datacenter applications
$5.99