With a competitive 30-month free replacement limited warranty and a terminal design that resists acid leaks, seepage corrosion, and black post, ACDelco Silver (Professional) 30 Month Batteries deliver maintenance-free performance and peace of mind. ACDelco Gold (Professional) 30 Month Batteries have an impact- and break-resistant plastic case for durability, including robust separator envelopes to help with auto battery life. Intelligent use of lead and acid provides optimal blend of cold cranking amps and reserve capacity for outstanding performance for automotive applications. Some ACDelco Silver parts may have formerly appeared as ACDelco Professional.