Scientists at Leiden University in the Netherlands flexed their 3D printing muscles to the extreme by shaping the smallest floating object in the world.

The tiny boat is a 30-micrometer replica of Benchy the tugboat — a jolly 3D printing test design — as an homage to one of the most popular 3D printer tests objects.

According to the Dutch engineers, the tiny boat is so small it could float down the interior of a human hair shaft. It can even propel itself thanks to a few platinum molecules that react with hydrogen peroxide, so it essentially boasts a full sailing system.

To print the most intricate part of the microscopic tugboat — the cockpit — the researchers focused a laser beam onto a droplet that hardened right at the focal point. By moving the laser beam in a highly precise and controlled way, they could perform the desired nanometric cuts.

The team at Leiden University embarked on this project as part of a grander research project investigating microswimmers, which are essentially any small particles moving in fluids. These include bacteria and sperm.

“3D Benchy is a structure that has been designed to test macroscopic 3D printers because it has several challenging features, and it was natural to also try it at the micrometer scale,” researcher Daniela Kraft told Gizmodo. “In addition, making a swimming micrometer-sized boat is fun.”

The findings were described in the journal Soft Matter.