The Mechanical Stone Mini Box with electronic board takes maximum power from the battery with no harm to button. The button is a stainless steel band. Also, the board has special overdischarging and reverse polarity protection. For 18350 battery.
Size: 25x31x55 mm Weight: 53 gr Material: stainless steel and natural acrylic stone Color: Blue/Brown/Red Velvet - new! Price: €99