The T-336 is a series of high performance, synchronous and asynchronous, full-duplex, multi-standard standalone or rack-mounted modem. It is designed for use on 2-wire dial-up and 2/4- wire leased-line circuits.

The T-336 is fully compliant with ITU-T V.34 recommendation as well as being compatible with ITU-T recommended V.32bis/V.32, V.22bis, V.23 and V.21 international standards while operating at 33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200, 4800, 2400, 1200, and 300 bits per second.

An in-band secondary channel allows the user to monitor and control the remote site unit. The T-336 series also offers auto callback and leased-line security checks in addition to the dial-up security checks.