Stontronics crt60 series stontronics crt60 2000 the stontronics crt60 series 2000va ups crt60 2000 utilises digital line interactive vi technology with a pseudo sine wave output this makes it perfect for smaller backup needs such as cctv epos small office hardware security or a simple pc workstation stontronics crt60 series 2000va ups crt60 2000