W21

Single-Row Ball Bearing with Flange (RK)
RK No Gear | RK Internal Gear | RK External Gear
Single-Row Ball Bearing without Flange (HS, HT, MT, XT)
HS: HS No Gear | HS Internal Gear | HS External Gear
HT: HT No Gear | HT Internal Gear | HT External Gear
MT: MT No Gear | MT External Gear
XT: XT No Gear | XT Internal Gear | XT External Gear
Double-Row Ball Bearing (DT)
DT No Gear | DT Internal Gear | DT External Gear
Crossed Roller Bearing (XR)
XR No Gear | XR Internal Gear | XR External Gear
Triple-Row Roller Bearing (TR)
TR No Gear | TR Internal Gear | TR External Gear