1.6F22 9V battery inside. 2. It can detect car lamp halogen bulb, G4, G5, G5.5, GY6.35, G13, MR11, MR16, GU10 bulbs, or test E10, E14, E26, E27, bulbs. Size: 110*64*40mm, 100PCS/CTN, 475*400*230mm, G. W.: 12kgs. More relevant about detectors please refer to our website. Cheap in price with quality.