These are the beautiful, self-propelled mechanical models designed and sold by Ugears. The kits come pre-cut out of plywood. The assembly process uses no adhesives, and all the mechanisms are powered only by rubber bands, cranks, and gravity.

The company’s press statement says their products are intended to strengthen the real-life bond between fathers and children (only slightly sexist, but whatever). They’re meant to move play away from the virtual of computers and into the actual of the physical world.

The kits take between one hour and half a day to assemble, and they look like a really great rainy-day activity. The finished models are good looking enough to display, too!