PAC LCGM24 Radio Replacement Interface for Select Non-Amplified Class with 24-Pin Connector Radio Replacement Interface for Select non-amplified Class II GM vehicles with 24-pin connector Retains all safety warning chimes when the factory radio is replaced Provides 10-minute RAP accessory output Interface can be quickly updated if needed from PAC website using PAC-UP USB adapter Retains all safety warning chimes when the factory radio is replaced Provides 10-minute rap accessory output 24-Pin connector