Mr. Gasket 2230G Headlock Locking Header Bolt， (Set of 12)<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Serrated teeth grip header flange surface providing a locking action</li><li>Thread-lock patch prevents header bolt torque loss and provides positive thread seal</li><li>Combination hex/socket head design for easy installation</li><li>Made from high-grade stainless steel to resist rust and corrosion</li><li>Material specification Grade 8， 150，000 PSI tensile strength</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51Xm%2Bqfc-hL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/51sevAHxwjL.jpg" noproxy>