Battery 4000mAh or 7000mAh
Battery with 2Amp fuse and lead/connector for TeensyBat detector.
Pic a capacity, the 4000mAh is 6x60x90mm the 7000mAh battry is 10x60x90mm.
The larger battry has can be used for longer time, the smaller battery makes the detector more comfortable to hold. Since the battery protection circuit is on the mainboard there is only a fuses used on the battery + terminal.
Do not use this battery for other projects that require to have deep discharge protection on the battery itself.