-Valve Spring Height Micrometer 1.600"-2.200" Height Range For V8 Engines 4929 -The quickest, easiest, and most accurate way to measure valve spring installed height and the easiest way to set upvalve spring!!! Features: -- Materials: Made of high quality Aluminum with black finish, great strengh and light weight , anti-corrosion , durable touse and no deformation. -- Quickest, easiest, most accurate way to measure valve spring installed height. -- Install just like a spring, then is expanded until it fully seats valve, locks and retainer. -- Simulated installation allows ultra precise readings. -- Tool is read like a micrometer and is accurate to.001 in. -- Range - 1.600 to 2.200 in. Before installing the spring on the cylinder heads, check the installed spring height 1. Install 1 intake and 1 exhaust valve. 2. Get the correct retainer for the spring and correct locks for the retainer. Pull the retainer tightly against the valve locks while holding the valve assembly steady. 3. Place 4929 height micrometer or a snap gauge and a pair of calipers on the valve between the spring seat and the outside step of the retainer and turn the height micrometer counter clockwise to establish valve spring height. After you have measured all the valves, find the shortest height. This will become the springs installed height on your heads. 4. Add shims until proper height is obtained on the remaining valves. Take the height micrometer and retainer to valve spring tester and check valve spring load at that height. Important Note: Since the retainer is installed in the spring when checking the spring loads, make certain that the thickness of the retainer is not included when calculating the installed height and is accounted for when compressing the spring. The spring load checker will show tobe higher with the spring installed at the correct height. Package included: 1 Height Micrometer Friendly Tips Due to manual measurement , there may be 1-3cm deviation exist,hope you can understand. There are slight difference between the picture and the real item caused by light brightness,hope you can understand.