I wanted this for the simple operation of some Equinox scanners that have a one channel option, and as this has a numeric readout it would be easy to use but I made two modifications, firstly I removed the smoked glass cover over the readout to make it brighter and clearer to read, and then I changed the awful bright white power LED to a nice dull red one. This didn't require changing the dropper resister, just the LED. Result, now very happy. Yes I know I voided the warranty....! It is now really good, simple small and easy, just right for my needs.