Most tracks are made from galvanized steel for rust resistance. Aluminum is a lighter, more corrosion-resistant alternative for lightweight doors.
How to measure: Find the junction where the vertical and curved tracks meet. Measure the vertical distance from that bottom point to the center of the horizontal track.
Replacement tracks are often sold in pairs for vertical or horizontal sections. Garage Door Tracks | Options, Headroom and Specs
Extends the vertical portion of the track so the door stays against the wall longer before turning back. This is perfect for garages with tall ceilings or those using car lifts.
