This replacement or spare magazine is compatible with your US M1 Carbine. It is constructed of heat treated steel with steel stamped mag follower and mag spring formed from chrome silicone wire. Made in the USA.
Specifications:

Caliber	30 Carbine
Capacity	30
Finish	Blued
Model	M1 Carbine
Material	Steel
Type	Detachable
Model Fit	M-1 Carbine
Brand Fit
Max Capacity	30