The gearbox of the trailer parking help is designed to provide further secure assist to prevent the trailer from tipping over throughout loading and unloading. It converts the input rotational power into vertical assist drive via a gear mechanism, providing additional stability.Structure of Trailer Stabilizer1.PLATE WELDMENT TOP 2.JACK,DRIVE 3.JACK,DRIVEN 10.CRANK,ASSY11.GRIP,PVC, BLK 13.SCR,HHMS 14.NUT,HEX 15.WSHR,FLAT 16.LABEL,REFLECTOR, RED17. LABEL,INSTRUCTION 18. LABEL,PRODUCT 19.GEARBOX 3WAY20.TUBE,DRIVE,JACKS 21.SCR,HHMS 22.NUT,HEX,NYLCK 23.SCR,HHMS 29.HANDLE,LEFT,FLANGED30.HANDLE,RIGHT,FLANGEDDimensional Drawing of Trailer Parking Support Gearbox