T-1 loopback cable
A loopback jack and plug is also a T1 loopback cable.
It is used to check the signal of a T1 line. It can be plugged in directly
to a line or attached to the end of the a patch cable.
A T1 loopback cable is an essential component for every T1 customer
to have on hand. It will help to ensure that a T1 connection is always
working properly. It is an important tool for troubleshooting as well.
A T1 loopback cable can be purchased at most computer supply stores.
These stores may be located on the Internet or in a local area. They
offer a large selection of T1 cables and accessories.