Product Details: With Expertise Built In™, the OTR Charge Air Cooler Tester Kit includes added heavy duty test plugs with cast handles that are flexible to fit six different sizes with two and a half to four-inch rubbers, pressure gauge, pressure relief valve, and a pair of safety clamps for operator protection. This heavy duty charge air cooler tester kit is designed and engineered to pressure test CACs accurately and safely. FleetPride is your First Click in Heavy Duty®.