Sealed Maintenance Free batteries (SMF); A sealed maintenance free battery which never needs to be refilled. The lids on this series of batteries internally re- generate any gas that occurs during use or charging. The battery construction is based on the use of lead-calcium plates, which yet further reduces the water usage. The models VESMF60, 70, 85 and 105 are equipped with a “magic” eye which indicates the state of charge. This new line of batteries are offered instead of the current range Vetus maintenance free batteries