These durable adapter pins work alongside our Teacher Geek line to convert a 3/16" hole to a 2mm motor spindle. They allow TeacherGeek components (connector strips, gears, pulleys, blade hubs, etc.) to mount directly on the motor. Adapter pins are made of a sturdy plastic that can withstand the heat from motors, without softening or falling off mid-use. An excellent addition to STEM | STEAM | Maker activities or science fair projects.