Heavy duty ndash equipped with extra power battery perfect for starting bigger engines selected as a ldquobest buyrdquo by which caravan magazine because of its feature packed specificationit is ideal for starting petrol engines up to 4 litre and diesels up to 25 litre included are 1m long leads for easier use allowing you to safely connect the jumpstart 4000 to your battery the audible alarm will warn you if you have incorrectly attached the leads to avoid damage while the intern