The Light my Bricks AA Battery Pack includes a connection cable that allows you to connect and power LEGO lighting components. Use this Light my Bricks AA Battery Pack when you need to power more than 20 individual LEDs. The dimensions of the AA battery pack are 68 mm x 47 mm x 17 mm. The attached connection cable is approximately 15 cm long. AA batteries are not included in this package. Light my Bricks offers LEGO fans an easy way to enhance their LEGO models with LED lights. All components in the Light my Bricks sets are plug-and-play compatible - no electronics knowledge is required for installation. Light my Bricks parts are small and delicate enough to fit between and under LEGO bricks.