Hudson Bearings drop in heavy duty ball transfer. Made of carbon steel material. Integral flange at top allows unit to be dropped into 1-3/4-inches diameter hole. 1-3/16-inches main ball rotates on 1/8-inches support balls. Ball support cup is machined from solid steel and is hardened and plated. Ball transfers solve a variety of material handling and motion control challenges, whether used in the traditional ball up position or as a caster in the ball down orientation. Ball transfers offer advantages to traditional casters, such as lower profiles and omnidirectional movement, often at a lower cost. Common applications: air cargo, shears, robotics, military logistics, store fixtures, die handling, laser and plasma cutters, glass and metal manufacturing, medical devices, caster substitution.