Size Chart:
33 - 8.0" Axle - Fits 8" - 8.125"
44 - 8.35" Axle - Fits 8.25" - 8.75"
55 - 9.0" Axle - Fits 8.75" - 9.125"
66 - 9.35" Axle - Fits 9.25" - 9.75"

Weight:
33 - 367.5g
44 - 396.5g
55 - 412g
66 - 419.5g