Hudson hdbtm-1 3/16 ss hd 1-3/16 stainless steel ball in stainless housing & metal cap drop-in hudson bearings is an innovative domestic manufacturer of ball transfers. this heavy duty drop-in unit is fully machined from solid steel and is hardened and plated with a metal cap. housing options include stainless steel. main and support ball options include stainless, nylon, phenolic, and delrin. integral flange can be dropped into a 1.800 inch diameter hole.