The Canon TC-80N3 Timer Remote Control is a remote switch with a 2.6' (80cm) cord and a self-timer, interval timer, long-exposure timer, and exposure-count setting feature. The timer can be set anywhere from 1 second to 99 hours, 59 minutes, or 59 seconds. A dial enables you to easily enter the numeric settings with a single thumb. The LCD panel can also be illuminated. The rear of the controller has a hole to keep the EOS-3's remote control socket cap.
Full Specs and compatability can be found HERE
Quick start guide can be found HERE
PLEASE NOTE: This remote will only work with cameras that have an N3 remote terminal (5D series, 7D series, 1D series, 20-50D).