Ensure your semi is Ready for the Road Ahead with a smooth and reliable spring-operated door assembly, with the Todco 4.5" Steel Roll Up Door Bottom Fixture. To prevent your door from wiggling when closed, this replacement bottom fixture tightly secures the components together. Fashioned with rust and corrosion-resistant metals for extended use in rugged climates and harsh conditions. FleetPride is your First Click in Heavy Duty .