Stationary batteries manufactured as 2V single cell.  Depending on usage location, cells are merged to create the battery group. These batteries come in two types as standard flooded type (OPzS) and Gel type (OPzV). Low-maintenance, Tubular Stationary Unit (OPzS) batteries are standby batteries manufactured to be connected to systems as an uninterruptable energy supply. For the user, float voltage operation system require minimum maintenance and low energy costs.