The carriage assembly replaces the carriage on various belt and chain drive openers using a rail for an 8-foot-high garage door. The straight arm is attached and included with the carriage. Use with Genie 8' high door opener models: SilentMax 1000, SilentMax 1200, IntelliG 1000, IntelliG 1200, ReliaG 650, ReliaG 850, 1028, 2028, 3020H, 3020H-B, 3120, 3022, 3024, 3042, 4022, 4024, 4042.