This is a remote switch with a 2.6ft cord and a self-timer, interval timer, long-exposure timer, and exposure-count setting feature. The timer can be set anywhere from 1 sec. to 99 hours, 59 min., 59 sec. The plug for connection to the EOS-3 has a quick-lock feature. A new 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.