Detailed Product Description

Jacks prevent up-ending semi-trailers when not connected to a tractor during loading and unloading with heavy equipment. Also used to level trailers parked on sloping ground and prevent landing gear from sinking into a soft surface. High strength steel construction. Zerk fitting for relubricating Acme screw. Meet OSHA regulations when used with wheel chocks.No. 2W877 and 1F144 Spin Top Jacks have a manually turned Acme thread screw which raises and lowers jack allowing fast installation and removal of jack.No. 2w877 has a 10" long lift screw allowing a 7" adjustment range. 14" dia. Heavy-duty dome shaped base provides maximum leveling stability.No. 1F144 has a lifting capacity of 40000 lbs. 11" adjustment range. 8" dia. Swivel head and 8" dia. Semi-pneumatic wheels.No. 3KR77 Medium-Duty Jack has an extra-wide 6W x 24"L lifting beam for greater trailer support. Two handles assist positioning jack under trailer. Two-way reversible ratchet for adjusting height. 40000 lb. Lifting capacity.