Omega 10500 - 50 Ton Side Pump Bottle Jack - Features: Easiest accessible pumping system eliminates off-center pumping force for the most efficient operation. Extra large base provides added stability and strength. Serrated heat-treated saddle provides generous lifting area and secure grip. Heat-treated extension screw allows low pick-up height adjustment and maximum lift height. U.S. Patented built-in by-pass device protects hydraulic system from overpumping damage. Unique cross-type forged release valve assures positive control. A wide, rugged base provides stability and strength. Critical stress points are reinforced in all models for added durability and dependability.