Trimming: Denotes how quickly and neatly trimmers cut grass around walls, trees, and foundations. Edging: Denotes the speed and neatness of trimming a vertical line along walkway. Tall grass & weeds: Reflects cutting power and speed in two foot growth. Handling: Responsiveness and balance while cutting. Ease of use: Includes ease of starting the engine, feeding out new line, use of controls, and handle comfort.
WeightWeight is rounded to the nearest tenth of a pound and doesn't include fuel, which can add 1/2 pound.
Engine sizeEngine cubic centimeters (cc), motor amperes (amp), and motor electrical voltage (volt) are from the manufacturer.
ShaftThe shaft transfers power from the engine or motor to the lines that do the cutting. Models with straight shafts offer longer reach, while those with curved shafts tend to be lighter and easier to handle.
Four-cycle engineUses straight gasoline and doesn't require an oil/gasoline mixture, as do the two-cycle engines found in most trimmers.
Dual lineTrimmers with two lines cut more quickly and can handle heavier growth than those with just one line, since they do twice the work with each pass.
Line diameterThe thickness of the cutting line, measured in hundredths of an inch--for example, .085.
ClutchA centrifugal clutch disengages the rotation of the cutting head when you're starting or idling the engine. This makes it easier to start and, while you're doing so, keeps the string from the ground, where it will kick up grass and dirt.
Rotating headLets you swivel the cutting head 90 degrees for easier edging, which is done vertically.