The M4 c-mag Drum is a very good looking MAGAZINE that completes your M4.
WITH A CAPACITY OF 2000 BBs, nobody will get in your way anymore.
The drum mag contains a pressure switch so that you can easily load BB's with one button
Incidentally, the drum is suitable for all M4 Replicas.
The batteries are, 4x AAA please note that they are not included
Note that with every magazine it can happen that the BB's do not feed properly on a certain brand of replica.
The advice is to try a different brand of magazine, in order to solve the problem.