Manufactured from nitrile coated spring steel layers. Stress formed embossment provides excellent sealing. Also provides stability and reduces cylinder bore distortion. Ideal for super charged, turbo charged, nitrous oxide and extreme compression ratios. For high performance street, drag race and oval track. Packaged individually. Product Features:They have a compressed thickness of .040 in.They fit small block Chevy from 1955-91Available in different bore sizes
