... -Maintenance free,adding battery acid is unnecessary, -FM serie valve Maintenance Free Lead-Acid Battery Charge for autos.CAUTION : lead acid battery 1.Avoid short circuit ... , 2. Risk of fire,explosion, or burn,3.Do not charge in a sealed ... battery terminal, 8.Make regular examination and use it in the valid date, 9.Do not recharge(omitted if rechargeable ...