For use with JET milling/drilling machines Item#s 144553 and 144554. Works With: Jet Milling/Drilling Machines, Includes (qty.): 52 pc. 6 - T-slot nuts 6 - Flange nuts 4 - Coupling nuts 6 - Step blocks 6 - Step clamps 24-Studs, 4 each (3, 4, 5, 6, 7 & 8 lengths), Case Included: Yes