BatteryGuard™ Prolong the lifeof your battery. Maximize your battery's performace. Excessive shock and vibration are two of the leading causes for battery failure. Megaware BatteryGuard™ sits under your battery and absorbs the gravity shock caused by excessive vibration and up and down bounce. Features: * Reduces up to 80% of the G-shock caused by excessive shock and vibration * Protect against premature battery failure * Fits up to Group 31 batteries * Fits virtually any size battery * Great for boats, automobiles, ATVs, Trailers or anywhere shock and vibration can damage a battery * Can easily be trimmed to custom shapes or sizes * Save money by protecting your battery investment