Formed by the same process used to create Hooker's premium stainless steel LS headers, these high quality, flat??faced flanges deliver excellent sealing and warp resistance. These 304 stainless steel investment cast flanges (constructed by a permanent mold process to ensure consistently precise construction) are offered in either 1??3/4?? or 1??7/8?? port diameters and fit all versions of LS engine. Sold in sets of two, they include premium Hooker gaskets and stainless steel header bolts.