[Andymon]

Originally Posted by Essness

They are grade 8 bolts. A grade 8 bolt will be marked with 6 hash marks on the bolt head,

http://www.boltdepot.com/fastener-in...ade-chart.aspx

You would be best ordering them from a place like Mcmaster,

http://www.mcmaster.com/#standard-cap-screws/=n8tf2p

This way you know you'll get the right grade and proper measure.

I've also found a decent selection at Tractor Supply and/or Farm and Fleet.

Good luck.

The bolts that came with the WDH, on the top of the bolt there are three lines and the letters CYI.