Of wooden construction, the sports aircraft was plywood-covered, with exception of the fabric-covered wings and rudder. For storage the wings could be folded rearwards. Powerplant was an American 46 hp Szekely SR 3-0 three-cylinder radial engine.
Construction was completed on September 15, 1936, and Viri's first flight was made by Urho Heiskala on September 29, 1936. It was registered OH-IIK on May 12, 1937, however, within a year the aircraft was lost in a flying accident at Porthaniankatu on January 1, 1938. The pilot, Aarre ("Aaretti") Niemisen, escaped serious injuries.
Span: 26 ft 3 in (8.00 m)
Length: 19 ft 8 in (6.00 m)
Empty weight: 772 lb (350 kg)
Max speed: 88 mph (142 kmh)