This is a Futaba BR4000 Battery Checker

FUNCTIONS PER APPLICABLE BATTERY PACK:
LiFe (Lithium Ferrite), LiPo/LiHV (Lithium Polymer), and LiIon (Lithium Ion):
NiCd (Nickel Cadmium) and NiMH (Nickel Metal Hydride):

USB 2.0 charge devices with USB 2.0

VOLTAGE DISPLAY ERROR:
±0.005V @ 4.2V

INPUT VOLTAGE:
1s – 0.8V-15V
2s-8s – 0.8 V ~ 4.8 V

Working voltage :
5 V ~ 36 V

CASE SIZE (EXCLUDING PROTRUDING PARTS):

80mm x 55mm x 19mm

WEIGHT:
59 g