This is the 3.7V 400mAh LiPo battery for the Helimax Axe 100 SS and 100 SSL Helicopters.
Features: Stock replacement battery for the Axe 100 SS heli series
Includes: Helimax 3.7V 400mAh LiPo Battery with white Mini Connector
mAh Rating: 400
Dimensions: 0.71x0.27x2.2 (18x7x55mm)
Weight: 0.42oz (12g)