This is a .40 size Airplane Engine by Thunder Tiger. It is made in Taiwan and comes with a 3-Year Limited Warranty. FEATURES: Dual ball bearing-supported crankshaft Schnuerle porting ABN (Aluminum Brass Nickel) piston/cylinder assembly Forged aluminum connecting rod with dual bushings Unique "squared" cylinder head design has more surface area than most conventional cylinder heads, for cooler runs Twin-needle carburetor INCLUDES: Engine, expansion-style muffler (with pressure fitting & rotatable outlet), glow plug, wrenches, decals, and instructions. REQUIRES: Prop, engine mount, fuel filter, and fuel (Thunder Tiger recommends fuel with castor oil). SPECS: Displacement: .398 cu in (6.52cc) Bore: .8228" (20.9mm) Stroke: .7480" (19mm) Power Output: 1.22 HP @ 16,000 RPM Maximum RPM range: 2,000 - 17,000 Practical RPM range: 2,500 - 14,000 Weight (w/muffler): 17.19oz (487g) Crankshaft thread size: 1/4-28 Crankcase width (for engine mount): 1.36" Overall height: 3.4" (87mm) Overall width (w/mount flanges): 1.97" (50mm) Overall length (backplate to front of drive washer): 3.39" (86mm) Recommended prop size: 10x6 (break-in); 10x6 (aerobatic); 11x5, 10x6 (sport and scale) 8/28/95eke ir/jl updt jxs 12/15/03 updt jxs 04/20/10