ARP 1902501 Harmonic Balancer Bolt Kit For Select Pontiac 350， 400， 455 CID Applications<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Ensures that the balancer is locked in position as the crankshaft flexes and twists</li><li>Rated at 200，000 PSI， which is considerably stronger than Grade 8 hardware</li><li>Compact and extra tall 12-point head eliminates the worry of stripping the head by accepting a deep socket</li><li>Features an under head length of 1.580， diameter/thread size of 5/8 -18， and a socket size of 5/8"</li><li>Includes a wide area washer that is 1/4" thick</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41XAJJSJFUL.jpg" noproxy>