FEATURE Door Construction 3 layer construction Panel Thickness 2â??â?? Exterior & Interior Steel 26-Gauge Insulation Type Polyurethane Warranty Limited Lifetime R-Value 15.2 COLORS White Steel Insulated Garage Door, Aluminum Alloy High Speed Hard Door, Aluminum Exterior Door Exporter Canada. Top Dog main productsï¼?high speed hard commercial door, sectional garage door and high speed fabric garage door. Top Dogâ??s commercial door can apply to industrial area, storage, restaurants, retail centers, and automotive service centers. The newest generation of Top Dog commercial doors can offer the ultimate in strength, security and safety. -