Ensure your semi is Ready for the Road Ahead with a smooth and reliable spring-operated door assembly, with the Transglobal 1" Steel Single Spring Universal Track & Operator Kit. Thanks to its finely-tuned design, this replacement kit helps keep your track in line when opening or closing your roll up door. Built with corrosion and rust-resistant metals for long-term durability in harsh conditions and humid climates. This 1" Roller 6" Radius kit contains: Single Spring Operator Assembly: TD-59292-243X57X96 x1 Horizontal Tracks: TG-49622-1 STD LH (CS) x1 and 49622-2 STD RH (RS) x1 Vertical Tracks: TG-49192-1-L STD LH (CS) x1 and TG-49192-2L STD RH (RS) x1 FleetPride is your First Click in Heavy Duty .