Lazy design.1. There is no power switch. Of course you'll want to chain them together for storage etc. The only way to turn off the power is to unscrew the battery cover until it breaks contact with the battery. However, the Cleaver's three-light design is counterintuitive. Flashing can work better.3. You need to remember the color code, otherwise you need to carry this small piece of paper with you when using. or you need to print it on a pen. WHY NOT PRINT THIS DAMN THING TO THE DEVICE YOURSELF? Otherwise. This is a good portable device to carry in your pocket.