Material could not be loaded. I work a lot with solar energy. I need to install switches and gauges on plastic battery boxes and wooden control panels. I like round switches (rather than rectangular ones) because they're the easiest to install with a tool like this step drill. It easily drills perfectly round holes (see video). This is a high quality drill. The incisors are sharp like a knife. It rotates perfectly on its axis, does not tumble. It cuts holes with virtually no breaks, which is important for flush mounting with my switches and meters. easy. Supplied in a practical plastic storage box. I can't find anything I don't like about this step exercise. I highly recommend it.