... excellent quality, good service, pretty competitive price this control board for two speed elevator, hydraulic elevator, and escalatorMain features ... collective) or 2-8floors (single collective),can add 2pcs extension board for more floors.·Suitable for elevator of single speed, 2 ... , or hydraulic type, with reserve for VVVF updating.·main board self-powered (AC11V or DC12V) and peripheral power supply ...