[1] Clayton Folkerts designed the "Mono Special" while working for the Mono-Aircraft Corporation.

In 1930, for the American Cirrus Derby, pilot John Livingston was hired, but Stub Quinby flew in his place after an illness.

In the 1930 National Air Races, Quinby placed fourth in the 650 Cubic inch class at 142 mph.

In the 1933 American Air Races, the aircraft was renamed the Folkerts SK-1, with modified lift struts and addition of wheel pants.

The aircraft won first place twice in the 350 cubic inch class, and third in the 500 cubic inch class piloted by Harold Neumann, and fifth piloted by Marcellus King.