Remove the complications that often result from unreliable rubber plugs or bladders with our heavy duty cooling system pressure test refill kit this kit will save setup time and provide precise test results. uses shop air to uphold continual pressure to the cooling system during testing and refill 4 quick disconnect vacuum attachments provide quick refilling of the cooling system and eradicates airlocks for use with freightliner, international, kenworth, Peterbilt, mack, Volvo, GMC and Sterling cooling systems Includes heavy duty vehicle adapters, pressure test regulator, vacuum refill attachment with tubing in a plastic case Fit type Universal Fit