This is one of our small custom plain steel u-bolts made domestically to our customer's drawing and tolerances. 5/16-18 rolled thread was requested with a .06 X 45 degree chamfer and undersized first two threads.  The center to center dimension was set at .81", inside length at 1.38" and thread length at .62".  Lead time was approximately 4-5 weeks since the customer was not in a rush to get the parts sooner.  Faster lead time was available in needed.