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