Description Grade 5 1/2-13 x 7-3/4" x 3/4" Zinc Hex Head Bolt is new and in excellent condition, not in original packaging. Bolt is 7-3/4" long with 1-1/2 thread length. Thread is 1/2-13. Hex head 3/4 flat to flat, 13/16" point to point with a 1/4" height.