This tiny coin cell battery holder is ideal for small portable or wearable projects. It holds two 20mm coin cells (2032 are the most popular size) in series to generate 6V nominal. (If you want only 3V, we suggest sticking a crumpled piece of tin foil in one of the slots.) 20mm coin cells are popula..
Your project may be free-as-in-speech, but that doesn't mean it has to be free-as-in-beer. This handy coin validator/acceptor module is just like the ones you've seen in arcades. This model has the cool ability to accept up to 4 different coins! For example, you can program it for 4 different US coi..