Sizes: 8", 10", 12", and 13"6-ply 100% maple Sonic Cut shells are cut shallower for the tight focus, articulation, and crisp responseIdeal for hard reflective indoor surfacesRounded bearing edges help eliminate unwanted overtones2.3mm SuperHoop II give increased strength and durabilityRedesigned aluminum alloy tension casings8 tension casings on the 12" and 13" (instead of 6)6mm case-hardened tension bolts permit the highest tension without failure40mm tom spacers allow close-in positioning for