This flywheel bolt kit is good for Ford engines 4.6L & 5.4L.  This flywheel bolt kit is by Automotive Racing Products (ARP).  Comes with 8 bolts and fastener assembly lubricant with is to clamp load specifications.  The socket size is 5/8 12 pt., the UHL or Under Head Length is 1.000", and the thread size is M10 x 1.00.  Washers are NOT included!  These bolts are built built better then OEM and includes everything you need to bolt in your flywheel.  One of the strongest bolts on the market.