Testo International Mains Unit (0554 1096) This is a universal power supply for Testo instruments, with a 100–240V AC input and 6.3V DC output, a 2.5m lead, and UK and European plugs included as standard. It powers the Testo 327-1, 330, 308, 335, 340 and 350 without issue, for use as the main power source or for charging the instrument's internal battery, and is suitable for international use. Key Features & Benefits Universal Voltage Range: 100–240V AC input, suitable for UK and European mains supplies. UK and European Plug Adapters Included: No need to purchase separate adapters. 2.5m Cable Length: Sufficient reach for most workshop and field setups. Wide Instrument Compatibility: Testo 327-1, 3