... 0:No teeth,1:Normal,outer gear 2:Special type 2:Bigger module, outer gear(6)--Code of installation hole ... 0:Both rings with installation bolt holes 4:Bigger module, inner gear 1:Both rings with installation screw ... :Inner gear, single-row ball A:bigger module, without A:normal(2)--Dia. of track center, mm (3) ... type(6)--Classification code No.of gear module A:Both rings with installation bolt holes A ...