This battery connector is for use with 9V batteries and features a 2.1mm DC barrel plug. The “center pin” of the DC barrel plug is positive and the outer barrel is negative meaning it is compatible with Arduino’s DC barrel jack. The battery snaps into the connector and has 110mm wires – just long enough to give you flexibility in battery placement, but not so long that the wires take up all of your extra space in your enclosure!

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