1) Sliding contact surfaces: Steel vs. PTFE sintered bronzed mesh.
2) Materials: Outer race is made of carbon steel, inner race is made of high chrome bearing steel.
3) Heat treatment: Without heat treatment on outer race. Inner race is quenched (hardened), and surface plated with chrome.
4)
Features of structure: Without oil groove or oil hole. Outer race
formed by extrusion. With a PTFE sintered bronzed mesh between outer
race and inner race.
5) Properties: Self-lubricated, good wearability, self-alignment.