Avengers 120rd Polymer Magazine for M4/M16 Series Airsoft AEG Rifles w/ Fake Bullet Window

"These magazines feed fine, but required modifications to lock into my m4 and still can have some issues.

- I have owned 5 of these mags and all of them have cracks present in the transparent bullet windows.
- The feed lips collide with the hopup causing the magazine to not lock into the weapon. This only occurs when inserting the magazine at certain angles.
- The mag catch cutout appears to be low causing the mag catch to not properly engage. This can be fixed by using a knife to remove material at the top of the cutout until it is flush with base the 5.56 bullet silhouette on the side of the magazine.

This is based on my experience using it in the Matrix "Calico Jack" Metal M4 AEG.