Stihl MS151 TC-E Professional Chainsaw Features: Service-Friendly Air Filter System The carburetor can be accessed without tools, so you can clean the air filter in a single step. Fold-Out Hook The fold-out hook serves as a carrying rope attachment for lowering the arborist saw and for security. When it is pushed in, the hook doesn't get in the way of your work or when it's in storage. Advanced Combustion Technology Four overflow channels swirl the fuel-air mix before ignition, allowing for optimum combustion and highly efficient performance. The result is lower fuel consumption and high torque across a broad rpm range. Anti-Vibration System Intense vibration at the handles of power tools can lead to long-term effects on blood vessels in the hands and arms. STIHL has therefore developed an effective anti-vibration system whereby the oscillations from the machine's engine are dampened which significantly reduces vibrations at the handles. Compensator This controller in the carburettor prevents the fuel-air mixture getting richer as the air filter becomes clogged. The correct quantity of fuel is delivered to the carburettor depending on the quantity of air passing through the air filter. This keeps the fuel/air ratio in the combustion mixture constant and hence also the engine power. The filter doesn't need to be cleaned until an appreciable drop in power occurs. Manual Fuel Pump (Purger) A small fuel pump delivers fuel to the carburettor at the touch of a button. This reduces the number of starting strokes required following extended breaks in operations. Side Chain Tensioner The tensioning screw can be found on the side of the chain saw through the sprocket cover. This removes the need for contact with the sharp saw chain. Ematic Chain Lubrication System The Ematic chain lubrication system ensures pinpoint lubrication of the saw chain links and guide bar rails. When used with STIHL OILOMATIC saw chain, it will provide maximum lubrication, longer wear and less oil consumption than conventional methods of chain lubrication. The Ematic system can reduce bar oil consumption by up to 50%. STIHL ErgoStart A genuine advance in easy starting. STIHL ErgoStart cuts the effort required to start the tool by half, while the starter cord can be pulled at just one third of the normal force. All it takes is 2 fingers and a gentle pull action. Tool Free Filler Caps Special catches on the fuel and oil tanks for easy opening and locking without the need for tools