The LED Keeper is packaged as a Kit that Diagnoses and Repairs LED Light Sets. It is the only tool in the marketplace able to repair LED light sets. It uses insulation piercing technology in order to illuminate functional sections. Through place markers provided the process of elimination is used to determine the problem bulb or socket. - Bulb and Fuse Tester - Bulb Puller - Two Universal Replacement Pods - 9V Battery Included