This is our special bolt used on John Deere tractor models A and B. It is a grade 5 Bolt measuring 5/8” x 2 1/4” . The head and thread lengths are unique to this bolt. The head fits a shoulder to enable one wrench tightening. The thread length is to be clear of the shear force between the cast hub and wheel disk. Our bolt comes with a 5/8” gr8 NF nut and stainless steel lockwasher. Finish on bolt and nut is yellow zinc chromate. We also sell as a complete set as GP-AA3819R6PK which completely attaches one hub to wheel disk. These bolts are identical to your original and made in the USA.