The best battery in this product line - the Optima Yellowtop S 5.5 deep-cycle high-performance battery. Based on Spiracell technology, the battery is ready to power all loads. At the same time, it offers up to 15 times better vibration resistance than any other battery on the market. Optima Yellowtop lasts up to three times longer than conventional batteries and is guaranteed to deliver uninterrupted power throughout the discharge cycle. The performance is cleaner while delivering a higher voltage output than conventional batteries. The compact design minimizes weight and simplifies installation when space is limited. The battery is completely sealed and leak-proof, withstanding extreme temperatures and has a long shelf life. It is also completely maintenance-free.