Review on LS Engine Valve Spring Compressor Tool Compatible with Chevy LSX Camaro, Corvette, Trans Am, GTO, G8, CTSV, GM Trucks - Fits 4.8L, 5.3L, 5.7L, 6.0L, 6.2L LS1, LS2, LS3, LS6 by Victor Garro

tool comes without instructions. I inflated the cylinder I was working on with compressed air. And a few times I tapped the top of the pen holders with a rubber mallet. Don't use a product image to understand how it works. The long jacking screw is specially angled. I used this tool on the cast heads of a 2004 Pontiac LS1 241 to install higher lift valve springs and valve guide seals. They give an extra pressure screw and the included nuts should hold everything together when storing the tool.