 The thump range uses two types of Li-ion battery the original battery was 120mAh which was later upgraded to a larger capacity 150mAh The Thump 2's were supplied with a slightly larger in size battery having the same 150mAh capacity.Oakley or Motorola does not offer any battery replacement or repair service for the Oakley Electronics range.The Oakley Thump 2 offers UV and blue-light protection.