The DMX512 Isolated Splitter / Amplifier is available in three standard configurations: three, five, or eleven outputs from a single DMX input. Each output is electrically isolated from the input, and every other output, by 2500 volt optical couplers. Each output has its own line driver and associated power supply.
Doug Fleenor once received one of these units back for repair with a note, "Unit was run over by a fork lift but seems to work fine." Doug Fleenor Designs tested the unit, and it did indeed work; they later learned that the fixture was used for an entire outdoor concert in that condition.
Doug Fleenor Design takes prind on the quality and construction of its products.