These are custom grade 5 u-bolts made to our automotive customer's drawing at 5,000 pieces.  The u-bolts were manufactured domestically in steel zinc material and heat treated to RC20.   9/16-12 rolled thread was incorporated on each leg at 1.625" in length.  The overall inside length was measured at 3.875" and the inside width at 1.565".  Material certs and heat treat certs were provided with the parts per our customer's specific instructions and the overall lead time was 5-6 weeks for the full order.