This is no chinese crap battery, this is certified 3S 1,200mah battery capacity with 18 gauge wire! Lipo no less so you will have plenty of power to keep going! These are rated at 25c continuous or 50c burst or in other words, providing in excess of 25 amps continuously! Way more than needed!
This will fit most blasters including M4A1 and G36. Comes with mini Tamiya connector. This is much more suitable for our blasters. It does mean however that you will need to change your plug over on your blaster.
Measurements are 115 x 16 x 19mm