These specialty overhaul balls are designed to be compact and highly-efficient--they add weight without increasing the overall length, ideal for low headroom applications. Because their weight is relatively low compared to larger, more traditional overhaul balls, they are best used on small truck cranes or applications where minimal weight is required. Angular contact bearings make for a smooth, low torque swivel motion. Machined from forged alloy bar steel, zinc plating inside and out for corrosion protection. Safety factor of 5:1.