Gear Cover Tata Rexin Gear Cover Tata ECG dustcap is a small cover used on the valve stem of a Truck or car tire to prevent dust or other small particles from entering the valve and damaging it. The dustcap also forms a pressure seal, helping to prevent deflation of the tire due to slight gas seepage past the tire valve. Ecg Autoparts provides Gear Dust Covers for almost all vehicles from Cars to Trucks. Dust cover Tata, Dust Cover Leyland, Gear Rexin Tata, Gear Rexin Leyland, etc.