*A: changed internal design.
*B: changed internal design.
*E: maximum capacity design.
*K: tapered bore , taper 1:12.
*K30: tapered bore , taper 1:30.
*M: machined brass cages, roller riding.
*MA: machined brass cages, outer ring guided.
*MB: machined brass cages, inner ring guided.
*TVPB: solid window-type cage of glass fibre reinforced polyamide, inner ring guided.
For example: 31319.31318,31317.SS22222MW33TT,SS22224KMW33TT