The Brake Thickness Gauge, No. 411-03218, from Ascot Supply, offers technicians a quick and easy way to determine the remaining thickness of a vehicle's brake pads without having to remove any of the wheel components, making it ideal for quick inspections and checks. It measures the distance between the backing plate and brake disc, and thickness is indicated with a color-coded gauge that reads green for 11mm or thicker, yellow for 8-10mm, and red for 8mm or thinner.