---improved safety and performance design. The Martin 2" (51mm) track/roller system is engineered for superior safety, strength and performance. Every 2" (51mm) track system is equipped with hemmed edges on both vertical and horizontal tracks, long-life (100,000+ cycle) sealed roller bearings, roller shields, and reverse angle shields. These features are significant safety improvements in protecting fingers, hands, arms, etc. ---available wind design. Martin 2" (51mm) track/roller systems have been wind tested and certified at the Hurricane Testing Laboratories in Miami/Dade Florida, and in other testing facilities. The Martin list price catalog displays the wind speed of each door and the optional upgrades available for the most severe hurricanes.

---extended warranty. Martin commercial 2" (51mm) track systems, when sold as part of a door, are provided with a limited five-year warranty. Martin residential 2" (51mm) track systems are provided with a limited lifetime warranty.

---Martin 3" (76mm) track system. Because of the above statements, Martin Door Manufacturing recommends its new, improved and certified 2" (51mm) track systems in lieu of the 3" (76mm) track systems for all applications. The 3" (76mm) track systems do not have available, hemmed edges, sealed roller bearings, roller shields, life cycle testing, wind load and wind speed data, hurricane tested roller shafts, etc. The small number of requests for certifying the 3" does not justify Martin Moor Mfg to pursue 3" (76mm) track certification when the company's 2" (51mm) track systems meet all certification standards.

Martin doors & hardware parts included with the company's 2" (51mm) track systems are tested to exceed 100,000 cycles, except springs. Residential door springs average 30,000 cycles. Commercial door springs average 20,000 cycles. Optional higher cycle springs are available. The recommendation applies to all Martin's steel sectional doors except Montana and Super Steel garage doors.