Also called as spring cotter, spring cotter pins.
There're two types, single coil type and double coil type.
Standard DIN11024, ANSI/ASME/GB/JIS or customized
Material could be SAE1070, 65Mn Spring Steel, Stainless Steel
AISI 304, SUS316, SS201

R type lock pin, used to lock other components of sharf, bore,  sollted nut, clevis pins, etc
Surface: galvanized, color-zinc plated, nickel, chrome, black oxide