EarthX ETX12A Lithium Battery with BMS. Replaces YTZ7S, YTX7L-BS, YTX7A-BS, YT7B-BS, YTZ5S, YTX4L-BS, YTX5L-BS The one and only lithium battery to have a full battery management system that protects from over discharge, over charge, short circuit, cell balancing built in and excessive cranking protection .No hazardous lead or acid. Can last up to 8 years. Very low self-discharge rate. Extremely light weight. Higher Voltage while cranking mean faster start. Wide operating temperature range, will not freeze or boil over.