Components that earn their place.

A 2-cell rechargeable battery holder is a plastic holder designed to securely hold two rechargeable batteries and provide electrical connections to a circuit.

An Arduino cable is used to connect an Arduino board to a computer for programming, data communication, and power supply.

A standard electronic power supply that converts household AC voltage (100–240V) into a stable 12-volt DC output at up to 2 amperes (24 watts). It typically features a 5.5mm x 2.1mm or 5.5mm x 2.5mm center-positive barrel connector.

A 9V 2A power adapter is an electrical device that plugs into a standard wall outlet (100V–240V AC) and converts it into a stable 9-volt direct current (DC) output capable of supplying up to 2 amps (18 watts of max power).

A 5V 2A power adapter is a 10-watt electrical device that converts AC wall power (100V–240V) into a steady 5-volt DC output with a maximum current of 2 amps.