Product Details: The OTR Type 20 2.5" Standard Stroke Air Disc Service Brake Chamber ensures Expertise Built In™, boasting the required high tensile strength and innovation needed for brake safety. This OTR service chamber boasts high quality material to not only meet, but also exceed OEM requirements by thoroughly transforming energy from compressed air to apply the right amount of force to your semi truck's brakes. FleetPride is your First Click in Heavy Duty®.