Prepare your semi truck's wheels with enhanced protection against oil, dust, and debris, with the OTR Lexan Propar Replacement Threaded Hub Cap with Expertise Built In. By attaching to the external frame of a wheel, this removable hub cap protects the lug nuts, bolts, and axles from harmful roadside materials. Built with sturdy metals and a simplified design for an easy-to-install or remove procedure. FleetPride is your First Click in Heavy Duty.