This is an extended version of the standard magazine release for the Bul Armory series. Like the Cleaver or Tomahawk for instance. Its a little bit bigger then the standard version and its ambidextrous. I just use PLA for this. Its easy to release the standard version and replace it with this one. It's cool to print in red. My working proto was printed in this color but I would advise red or black.
Have fun shooting!