This is the glow powered O.S. 81FS-a 4-Stroke Aircraft Engine.

FEATURES: Same mounting dimensions as the O.S. Max FS-70 Surpass
          Ideal fit for 60 size planes
          Specially designed lubrication system eliminates need for crankcase
            ventilation
          60RA carburetor
          F5030 muffler with rubber O-ring in multi position manifold to help
            prevent oil leakage

Propeller: Sport and aerobatic scale 13x7-9 or 14x6-7

SPECS:    Displacement: 0.809 cu in (13.26cc)
          Bore: 1.091" (27.7mm)
          Stroke: 0.866" (22.0mm)
          Weight with Muffler: 19.63oz (556g)
          Practical RPM Range: 2200-12,000
          Output: 1.3hp @ 11,000 RPM
        

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