Review on OP/TECH USA Battery Holster: Compact SLR Battery and AA Batteries Case by Andrea Beavers

This bag was easy to attach to my camera strap. It's designed to fit over the end of the strap instead of connecting with a fold and snap. This should help keep the holster from coming loose unless the strap detaches from the camera or breaks. In that case, you have a much bigger problem than trying to figure out where your battery has gone. This makes changing batteries quick and easy as I don't have to get back in the car and pull one out of my bag or, when I'm carrying my Lowpro Sling bag, take the bag off my back and lift my camera bag. Remove the battery from the inside pocket.