Product Description 12 Bolt Built to Order Housing & Axle Packages. All Moser 12 Bolt Housings are designed and manufactured in the U.S.A. using Moser Engineering owned Casting Boxes. Package includes; New Moser 12-Bolt Made in the U.S.A. Housing, with OEM located mounting provisions, seamless steel tubing (3" O.D., 1/4" wall), custom alloy axles (30, 33, or 35 spline), bearings, studs, seals, heavy duty retainer plates, new housing ends and t-bolt kit.