Vetus batteries are manufactured specifically for use on board recreational boats - a successful combination of starter and consumer battery! The Vetus battery is about 25% lighter and about 40% smaller compared to conventional batteries with the same capacity. The self-discharge is only approx. 4% compared to approx. 13The special design of the maintenance-free Vetus battery eliminates the need to refill the electrolyte. The battery housing is closed, a sight glass provides information about the state of charge. Vetus batteries are delivered filled and charged.