These transformers are rated for intermittent operation at their maximum listed power capability for a duty cycle of 25%. I.e. 5 minutes ON 15 minutes OFF. They may be used in a continuous operation mode at a rating of 50% of their maximum capability. E.g. a 3.3KVA unit may be operated continuously at 1.65KVA Primarily for use when using portable electric tools on outdoor sites. Tool Rating 3300 VA. Output Sockets. 2 x 16amp. Manufactured to BS3535, Thermal overload protection, BS4343 output sockets as standard, Glass reinforced polyester case, Input flex & 13 amp plug