Airfix includes two gun turret interiors – a single-gun version, and a twin-mount. The two-gun mount is one of many uncalled for spares in the kit that point to future releases. Note also the large ejector-pin mark in the seat of the twin-gun mount; I sliced off part of the seat on the single-gun mount instead of trying to fill the gaping hole. Also, my gun mount was broken. I replaced it with a mount cut from the unused twin-gun part.