Here's a really nice package from BOYI.  The 3081B M4A1 style full auto AEG replica carbine featuring the following:  Full or semi auto select, hop up, extending/retracting stock, 40 round mag, battery and charger, sling, speed loader, safety goggles, and more.  Delivers approx. 200fps muzzle velocity @ about 350 rpm (rounds per minute).  Weighs in at a healthy 6.2 pounds of rock-n-roll fun.