Ensure your semi is Ready for the Road Ahead™ with a smooth and reliable spring-operated door assembly, with the Whiting 7.3" Steel Roll Up Door Security Lock Assembly. To keep your cargo safe and in place, this replacement lock assembly is crafted with ultra-secure components. Constructed with rust and corrosion-resistant metals for extended use in harsh conditions and humid climates. FleetPride is your First Click in Heavy Duty®.