Pilz - Safety, PNOZ X4 120VAC 3n/o 1n/c. Safety relay (standalone) Inputs: 1-/2-channel wiring with/without detection of shorts across contacts Outputs: 3 N/O, 1 N/C. Automatic/monitored start UB 120 V DC, width: 45 mm, integral screw terminals, Monitoring E-STOP, safety gates.