... from 20mm to 600mm, or 1-1/2" to 26". T bolt for concrete sleeper 1. Standard: TB, AREA or ASTM ... ". 3. Grade: 4.6, 4.8, 5.6, 8.8, 10.9, Gr2, Gr5, Gr 8. 4. Protection: Black, White zinc ... : Gunny bags+ wooden pallets, wooden case or cartons+ wooden pallets T bolt