So I got this gun right. Well on the box it says 260 fps with .2. Maybe 310 is with .12, I dont know. Guns made of plastic except for the sling mounts and the mag. It has hop-up. You first have to lever behind the rear sight back. Then you can adjust it. It has maybe 4 rail mounts. You should charge the gun before firing (getting the cap off is kinda hard). The place to put the batteries is in the buttstock. Comes with a sling and can hold around 250 bbs in the mag. Has saftey, single, and full auto selector switch. Good gun for starters i guess. Well happy airsofting.
*EDIT
This gun actually shoots around 300fps. Checked the fps at tac city. It is light for its size. Think before you actually buy this gun because you might want different guns. The ROF is pretty slow. The sling mounts are weak and mine broke already. Charging the battery takes about 6 hours. It hasn't overheated for me yet but keep an eye on it while it is charging.
PRO:
4 rail mounts
comes with hi-cap mag
shoots 300fps
CONS:
slow ROF
weakish sling mounts
a bit to light for my taste