The 
Rebel 11.1V 600mAh 20C LiPo battery
 with a Deans connector is a compact, high-performance battery designed primarily for airsoft guns with limited internal space, such as PDW (Personal Defense Weapon) and SMG platforms
 
The battery has the following key specifications: 
Type: Lithium Polymer (LiPo)
Voltage: 11.1V
Capacity: 600mAh
Discharge Rate: 20C (typical)
Connector: Deans (T-Plug)
Configuration: Micro/PDW style
Dimensions: 16mm x 16mm x 75mm
Compatibility: Specifically designed to fit the EMG Autobot Speedloader and other tight internal compartments.