These extra thick dual port intake gaskets feature accurate die cutting that will fit your intake exactly. Their shape has extra material for heads that are ported and polished. If you have stock heads, just trim off the extra material on one side with scissors. An advanced anti-stick coating is applied to the material, so you can re-use the gaskets several times. Unlike some cheap gaskets, the stud holes are the exact size and shape needed to prevent shifting and mis-alignment. Please choose to purchase by the pair or by package of ten.