The Sealey AK500 Car/Van 12V Battery and Alternator Tester features an LCD backlit display that verifies the condition of the battery and alternator output. It is suitable for 12V DC systems and connects to the vehicle via the accessory power socket (cigarette lighter socket). The tester is fitted with a 250mm cable and is powered by the vehicle's connection. This device helps in analyzing the battery and alternator performance for cars and vans.