I can't tell you what size they are, but I know they are hard to find. I while back I found some at a specialty bolt store and they fit tight. You may be better off going to the stealership for bolts.
Good Luck
Good Luck
Per Nissan's info site, Nissan Publications the torque setting is 101 foot lbs.I pick up my tow hitch on Craigslist for $40 but it did not come with the bolts but i went to U-Haul and pick up a blot kit the kit number is 78274 for $15with the kit it give you (6)1/2 washers and (6) m12-1.25x40mm hex Bolts and the torque 65 lb-ft.I also needed to relay the dealer wanted $50 for them but U-haul had a relay kit #13804 for $24.95 it covers from 2004-current. Hope this help out some one.