Abstract: A demountable wheel optionally mountable on a hub equipped with cyclindrical studs and on a hub equipped with tapered studs. For this purpose the wheel is provided with a first ring of bores accommodating hubs having cylindrical studs and with a second ring of tapered bores accommodating hubs having tapered studs.

Abstract: A shock and vibration-proof fastener of general application and particularly suitable to hold dual wheels demountably assembled to a cargo vehicle hub. The fastener is designed to isolate the threads thereof from radial and torsion stresses utilizing a split collet encircling the shank of the fastener with its periphery converging toward the collet ends at angles of the order of 4 to 1 relative to the collet axis and having a nesting interference fit with a similarly tapered bore through the parts or wheels to be clamped together. The fastener shank has a threaded well in one end mateable with a cap screw having a self-aligning conical surface on the underside of its head engaging the rim edge of a loose fitting washer. The self-aligning surfaces are preferably provided with a ring of teeth and notches interengaging along helical surfaces having a pitch substantially greater than that of the fastener threads.