U.S. Patent No. 7,171,807Air/hydraulic foot pump provides hands free operation and easy, convenient lifting.Metered pump valve provides safe lowering of load.Fully adjustable universal saddle with hand adjustable corner brackets and safety chain.Safety overload system prevents jack from being used beyond its rated capacity.Two-stage flash chromed rams inhibit rust from entering hydraulic system.Wide base with four easy rolling 4” diameter polyurethane, swivel ball bearing caster wheels (one is a locking caster wheel) provides stability and easy maneuvering in its lowered position.Polyurethane wheels provide protection for expensive tile and epoxy floors.