The record contains a metal box with removable circuit cards at the back. The cards are labeled "DISCRIM.", "MOD.", "HYBRID", "Limiter", "TIMERS", "ANS. BACK", "KEYER." There are also numerous test points. The other open side, or front, shows seven relays. All of these parts are covered by a metal case. On each side there is a cables. At one side the cable ends in spade lugs and phone wire. At the other end the cable terminates in a female Winchester connector.