The M1 Carbine was also an American service weapon, but is not to be confused with the popular M1 Garand. The latter gun had a larger, detachable magazine instead of the stripper clips used by M1 Garands. This feature allowed soldiers to shoot rapidly and have less time between magazines.
The Well D69 is an airsoft replica of the famous M1 Carbine and features a magazine that can hold up to 180 BBs.
Made from plastic, its much lighter than the original metal magazines. Thus, you dont have to worry too much about the weight.