The M3-AD-M1 Converts a two-pin Motorola connector (M1) for use on Motorola EX series radio models.
The M3-AD-M1 adapter is compatible with these OEM Radio Models:
Motorola: EX500, EX600, GL2000, GP328Plus, GP338Plus, GP344, GP388, PRO5150elite
Relm: RPV3000, RPV3600, RPU3000, RPU3600, RPU4200