Aluminum, Copper, Steel, High Temperature RTV
An Apollo Command Module Earth Landing Pyro Continuity Verification Box (PCVB), operated in series with the Earth Landing Sequence Controller (ELSC), provisioned to monitor the pyrotechnics responsible for jettison of the Apex Cover (forward heatshield), and deployment mortars associated with the Drogue and Pilot parachutes. The box includes a Ground Support Equipment (GSE) access connector for ground checkout of ELS pyrotechnics. This unit was a subsystem of the SECS (Sequential Events Control System).
System redundancy was achieved in a single unit (unlike the MESC/ELSC which had two boxes per subsystem).