Until now the only way to compress the Cummins 5.9 valve springs was to use a Lisle or KD tool. They are fine tools but require twice the work because you have to do one valve at a time. The problem gets worse when you tackle number 5 and 6 cylinders. The limited room under the cowl makes it difficult to use these tools in this confined space. The CVSC020 is only one inch taller than the valve springs, which gives you more room to work, on the back two cylinders. And you can replace your Cummins performance valve springs in half the time! This is what you get in the CVSC020 kit. One machined bridge and top plate, mounting hardware and a 6mm Allen wrench along with complete instructions. The tool will pay for itself in time savings alone.