The format of my studio is so called 'one man, one room'. The first time I thought about dummy plugs and dust covers when quantity of equipment in there exceeded a dozen. Cleaning the equipment had became a big problem. The dummy plugs from Neutrik have been a great solution. NDD for DIN- (MIDI), NDP for RCA-, NDJ for Jack-connectors are totally protect them. Made from quality and pleasant to the touch rubber the dummy plugs have a comfortable heads to put in and extract. However these heads may be a problem. For some devices the connectors itself are standing out from the bodies, plus sized heads of dummy plugs. These protruding parts could be a hindrance for working, carrying and packing in cases. In any way I find these dummy plugs very helpful and use them anywhere.