This is a rechargeable 4.8V NiMH battery pack with a capacity of 900 mAh. The pack consists of four AAA cells in a single row and a 4" lead terminated by a “JR”-style connector.
This battery pack comes with 4" leads terminated by a 3-pin JR-style female connector (only two of the pins are used). The connector is the same as what is found on the most servos and has a 0.1" spacing, so it fits nicely with 0.1" male headers and can plug directly into most RC receivers, servo extension cables, and servo switch harnesses, and custom cables made with JR male connectors or Futaba J male connectors.