This specification is used for general engineering and when a bolt requires the specifications of A325 but exceed 1-1/2” in diameter (A325 spec only ranges from ½” – 1-1/2”). A449 ranges from ¼” to 3” diameter bolts. There are two types of A449, Type 1 and TAype 3 (there was a type 2 but it was withdrawn in 2003). Similar Specifications are A325 and A490. This Spec can be used for Hvy Hex Bolts and Anchor Bolts.

Type 1:
Plain carbon steel, carbon boron steel, allow steel or alloy baron steel 
Type 3:
Weathering Steel 

Recommended Nuts for Type 1: 
1/2″ to 1-1/2″ Plain: Hex, Grade B 
1-1/2″ to 3″ Plain: Heavy hex, Grade A 
1/4″ to 3″ Galvanized: DH, Heavy Hex 

Recommended Nuts for Type 3: 
1/4″ to 3″: C3, DH3, Heavy Hex

Recommended Washers for Type 1 and 3: F436