Valve spring inserts are an important component of air compressors, which provide air supply to different parts of the engine where needednside Diameter (mm): 6.4 Length (mm): 15.2 Width (mm): 15.2 Inside Diameter (in): 0.25 Cross Section Height (mm): 3.8 Height (mm): 12.7 Weight (kg): 0.05 Cross Section Height (in): 0.15 Cross Section Width (mm): 4 Cross Section Width (in): 0.16 Material: NBR - Nitrile Material Description: NBR is a versatile material with good abrasion and cut resistance. It works well in Air, Engine Oil, Diesel Fuel, Coolant/Urea, Hydraulic Oil and Automatic Transmission Fluid applications. Do not use with Biodiesel. Notes:: Dimensions and Material Descriptions provided for reference only. Color may differ from image.