The Arri HMI M40/25 set 2,5KW is the version with 2500W HMI burner. Here a normal household socket with 16Ah is sufficient for operation. The Arri M series combines optimized weight and lightoutput with smaller size and more felxibility becaouse you can use two different lamps inside one fixture. This gives you more variety of lightoutput on set. The M40 in this 2,5kw version needs just a regular household 16 Ah plugg to run, but the same lamphead can be set up with a 4kW lamp for more lightoutput ( requires a 32AH blue plugg on Set.) This makes it an ideal lamp when changing of location might occour and your not shure which power you will have there. Just order an optional set of 4kw burners with this set.