Submited By: daniel p. on 01/11/2013 I'm using these with a KWA KM4A1, and they feed flawlessly. They fit the magwell very well, and are very sturdy. Don't let the "polymer" fool you, these are not your typical plastic mags. I would go so far as to say that these would probably hold up better than many metal magazines I've seen. Another thing, they are ranger plate compatable! | |