The M3 CLS Bag is lightweight nylon, similar to the same material the thin butt packs are made from. There are no molle provisions on it, nor the earlier belt clips. It's a good bag, but is "limp" like the butt packs are.
The version I'm using is an old Mil-Spec Plus bag. Condor, VooDoo Tactical and others made similar bags. These are made from heavier nylon, are a bit more rigid, and have molle loops and two built in straps on them.
Have used mine for my Johnny Stewart predator caller. The large compartment holds the speaker and its cable. One small compartment holds the caller controller, the other holds all the sound cards. Been using this bag for a long time. Don't recall exactly when it was purchased, probably early 2000's. Despite seeing a fair amount of field use it still looks like new. Been very happy with it.