0-9 & A-B
C-D
E-H
M-N
O-R
S-T
U-Z
Fits both the first gen (R50, R52, R53) and second gen (R55, R56, R57)
Standard SPF4474-80K / SPF4474-90K - Fitting Instructions
2 Degree Caster SPF4476-80K / SPF4476-90K - Fitting Instructions