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Review confirmed by purchase 
For those wondering if it fits the green gas KP-13 magazine from KJW, unfortunately, it does not fit. The hole for the pin is in a different location. After filing down the element and enlarging the pin hole, the part goes into the magazine, but unfortunately, the BBs get stuck in the jaws, so they are not properly fed into the replica. It's possible that after filing down that part, they won't get stuck, but unfortunately, I haven't checked this.
