We have seen a geeky clock powered by Apple or Orange, and have also seen a clock powered by water only. This geeky calculator is using the same technology, where it can extra the energy out of water using two electrodes inside the batteries made from a special allow.
The calculator has 3 batteries, each battery filled with water will fully used up about 2 to 3 months. It’s very practical, eco friendly and you’ll never have any supply shortage because water can be found just anywhere!
This geeky calculator is only $11 and you can get it at perpetual Kid.