Thousands of people in Sweden have opted to trade in their ID and credit cards for tiny microchips implanted underneath their skin.

The chips, which use near-field communication technology, take the place of key cards, rail cards and credit cards. They are typically the size of a grain of rice and are implanted just under the skin between the thumb and forefinger.

So many Swedes are lining up to get the microchips that the country’s main chipping company can’t keep up with demand.