Bendix K151065 is a genuine T30/30 spring brake for S-cam air brake systems. In normal driving, air pressure holds the spring compressed and out of the way of regular service braking. When that air is released from the chamber, stored spring force takes over and applies the brake, which is how the unit holds a parked vehicle and gives a fail-safe stop if air pressure is lost. It is a genuine Bendix part from Pro Gear and Transmission. Not sure which spring brake your axle takes? Call us and we will help you confirm fit.A factory handling fee of $20.00 per unit is added at checkout.FeaturesBrand: genuine BendixPart number: K151065Spring brake for S-cam air brakes, T30/30Air pressure keeps the spring compressed during normal drivingReleasing the air applies the brake for parking or an emergency stopTech SpecsType: Spring brake (S-cam)Model: T30/30