Ryobi RCS5145B Petrol Chainsaw has a powerful 2 stroke 51cc POWR XTTM Full crank engine that delivers outstanding durability and performance. The three point anti-vibration isolation provides additional user comfort and reduced fatigue during prolonged use. Also has a fast acting inertia activated chain brake for increased safety. Other features include an automatic chain and bar lubrication, clear fuel and oil tank for easy view of fluid levels, tool less air filter access, and a convenient and robust side access chain tensioner. Specifications Input Power: 51cc Petrol 2 Stroke.Capacity of Tank: 0.575 Litre.Capacity of Oil Tank: 0.35 Litre.Chain Bar Length: 45cm.Chain Speed: 22.2m/sec.Engine displacement: 51cc.Weight: 5.3kg.