BikeMaster AGM Platinum II Battery MS12-16AL-A2 Absorbed Glass Mat captures electrolytes and this technology means longer storage life and higher performance than standard wet batteries. Permanently sealed after filling means its maintenance free and non-spillable with no need to constantly check level or add water. Greater cold cranking amps, longer service life and resists sulfation. 1-year manufacturers warranty. Once activated, requires charging during prolonged storage periods.