Single seg tools are avaialble in 5 different bonds, and 4 different grits, refer to the table below

Extra Soft
XS-16/20
XS-30/40
XS-60/80
XS-120/140

Soft Bond
S-16/20
S-30/40
S-60/80
S-120/140

Medium Bond
M-16/20
M-30/40
M-60/80
M-120/140

Hard Bond
H-16/20
H-30/40
H-60/80
H-120/140

Extra Hard
XH-16/20
XH-30/40
XH-60/80
XH-120/140

