"Obviously these will probably only fit in AEG's that have full stocks. With that being said, this battery has lasted me a full 6 hour game day in my KWA SR12. That's with going through about a whole 5000 bag of bb's. I shot mostly on full auto but around 25% of my shots were on semi. It still had tons of life left in it, even after that whole day it still made my SR12 fire at full rpm. That alone made me buy another for future events where more shooting may be required."