... ABS cover -belt drive rail -soft start,soft stop Advantages: 1. Electronic limit switches2. Automatic safety reverse3. Manual release in case ... failure4. Chain drive , belt drive, low noise5. Power to lift the heaviest residential door.6. Provides light for safe entry into ... smooth and quiet running.3)belt drive steel track to get much quieter work4)work with photo beam,keyless pad, back-up ...