ASME B18.2.1 : 2012 Title: Square, Hex, Heavy Hex, and Askew Head Bolts and Hex, Heavy Hex, Hex Flange, Lobed Head, and Lag Screws (Inch Series) ISBN: 9780791834985 Pages: 44 Year: 2012 Publisher: The American Society of Mechanical Engineers Availability: Within 1-2 working days