NOVA 6025 Mini Step Chuck Accessory Jaw 2 Step sizes for optimum gripping of bases with minimal crush damage to wood plus internal spigot grip Internal spigot grip for small unsupported or supported spindle work Same jaw fixing system across all NOVA Chuck models - total system interchangeability All NOVA Chuck accessory jaws are designed to hold in the expansion and contraction modes Special NOVA dovetail profile, designed to maximum strength and holding in wood turning, without crushing wood fibers