You Need It, Bolt Depot Has It!
I was in need of 9/16" Grade 8 Bolts that were 4 1/2 inches. All I could find in 2 of my local box stores was even sizes, no 1/2 sizes of that size bolt. Bolt Depot had them in stock and shipped them quick. They show diagrams of the bolts which include shoulder size and thread length which was crucial to my installation. The price wasn't bad either.