These are custom low head socket cap screws we supplied to a customer at just 10 pieces, made in the USA using 303 stainless steel material. It incorporates coarse thread of 1/2-13 and has an overall length of 8-1/2 inches. The threaded portion of the screw is at approximately 3 inches in length to the customer’s specific requirements. Material certs were made available with the parts and all ten pieces were dimensionally inspected prior to shipment. Our internal part number for this low head socket cap screw is SCS-050136-I. Larger volume production would require a different factory and longer lead times: a US based factory would carry a lead time of 5-7 weeks while an overseas factory would typically carry a 130 day lead time for the first release.