ASP FS400AR 65cc 5R Radial. RC Model Plane Glow Four stroke Engine. Stroke:23.2mm x 5 (0.913 in). Bore:26.5mm x 5 (1.043 in). Full-Featured 4-Stroke Engine. RFS (Ringed Four-Stroke) Engine. Iron Ringed Aluminum Alloy Piston.
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