This Switched Battery Holder takes 4xAAA batteries and has two wires for connection into your project, or adding of a connector (not included).
The batteries are fully enclosed in a plastic case, secured in place by a small screw. The unit incorporates a small on/off switch. The leads are approximately 130mm in length and colour red and black to show the polarity for the connector.
With alkaline batteries, you'll get a nominal output of 6v, and 4.8v with rechargeables.