This ARP is the world leader in fastener technology. When investing in expensive high performance engine components, you do not want to take the chance on loosing a rod or main cap to a faulty or weak bolt! A warped head is a high price to pay for using a less than adequate head bolt or stud. With ARP you can gtrust that your parts contain the strongest, most reliable oem replacement fastners available. Don't cut corners...get the best you can get! Add the felpro upper and lower head gaskets and you have yourself covered!