Another thing about the PEQ battery boxes. They tend to be larger than mil spec and when/if you mount the battery box on the top rail of your gun, it blocks the front post sight. If you're running an 8.4v battery, I would assume the battery box would be smaller, but I have no experience with 8.4v batteries. Just 9.6v batteries
To answer your question, the battery box does add a little bit of weight to the gun. Like the above mentioned fact and this combined, its why I switched to a rear wired crane stock option.
G&P makes a mil spec (kinda) working PEQ. Working flashlight, working red beam powered by either AA or AAA batteries. I'm gonna get that next since I don't have a battery on my rail anymore.
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