I used this to troubleshoot my Cat 303.5C. The quick connection fitting was a perfect match for the machines test port. I only used that one fitting and the 0-5000 gauge, there wasn't any leaks and it worked perfectly to troubleshoot. The case doesn't seem to be all that well made, but if you store it in the tool box and not the bed of your truck I think it will last. Overall for the money you cant go wrong with this kit.