Insert four D cells (also known as D size batteries) to get a 6-Volt, long lasting battery pack. D size batteries last much longer than C size, AA size and AAA size batteries. This battery psck holds 4 D size cells in a 2x2 arrangement connected in series in order to create 6 Volts (While individual cells are 1.5 V each).
Color coded connection wires are 15 cm (about 6 inches) long and they are stripped and tinned 4-mm on ends.
Overall size is 134mm x 74mm x 32mm. It has 10 screw holes at the bottom in case you need to mount the box using screws.