This is the OS Engines GT22 Gasoline Powered Engine with Muffler and Rear Mounted Carburetor. FEATURES: Beam mounting design allows engine to fit inside cowls that are sized for 2-stroke .60-.91 and 4-stroke 1.20 glow engines Custom designed rear mounted Walbro carburetor with choke rod guide integrated into crankcase that minimizes set-up time IG-02 electronic ignition handles 4-6 cell NiCd, NiMH or 2-cell LiPo and LiFe batteries Pitts style muffler has reinforced mounting bolt holes and webbing at high stress points Two year limited warranty through Hobby Services beginning at date of purchase INCLUDES: GT22 Engine with Muffler, Electronic Ignition Module, CM-6 Spark Plug Muffler Gasket, Muffler Bolts and Instruction Manual REQUIRES: 2-cycle oil with a mix ratio of 50:1 if using Klotz model oil (if using other brand, follow manufacturer"s mix ratio or if no recommendation, mix at 30:1) Ignition Battery: 4-6 cell NiCd, NiMH, or 2-cell LiPo LiPo battery requires voltage regulator Propeller: 16x8, 16x10, 17x6, 17x8, 15x10 for break-in Gasoline safe fuel tubing and fuel filter SPECS: Displacement: 1.35 cu in (22 cc) Bore: 1.26" (32mm) Stroke: 1.08" (27.5mm) Practical RPM Range: 1,800 - 9,000 Output: 2.66 hp @ 9,000 RPM Weight: Engine: 26.86oz (761.6g) Muffler: 4.68oz (132.6g) Ignition Module: 3.7oz (105g) Initial Needle Positions: High Speed Needle-two turns open Low Speed Needle-one and a half turns open Distance Between Mounting Hole Centers Same Side: 0.98" (25mm) Distance Between Mounting Hole Centers Opposite Side: 2.2" (57mm) Mounting Hole Diameter: 0.197" (5mm) Length of Muffler Can: 3.9" (100mm) Width at Mounting Tabs: 2.7" (70mm) Width of Crankcase Below Mounting Tabs: 1.9" (49.4mm) Height from Crankshaft Center/top of Cylinder Head: 3.7" (94mm) Height from Crankshaft Center/Muffler Mounting Hole Centers: (48.4mm) Length from Drive Hub to Carburetor: 5.5" (139.5mm) Length from Drive Hub to Center of Crankcase: 2.7" (68.5mm) Length from Center of Crankcase to Carburetor: 2.8" (71mm) Crankshaft Size: 5/16-24 UNF-2A jxs 10/11/12 ir/jxs jxs 10/11/12 ir/jxs