This Gasparin G-10 CO2 motor has a 9.82 cubic millimeter displacement. The bore is 2.5mm, stroke is 2.0mm, and it weighs 4 grams. This engine is Serial No. 567, Built 10/21/99. Stefan Gasparin of the Czech Republic is listed in the Guinness Book of World Records as maker of the smallest engines to power flying aircraft. This engine came from the collection of Edward Swenton Sr. and is on loan courtesy of Edward Swenton Jr.