ESSENTIAL TERMS AND DEFINITIONS * POLE SAW A tool designed to prune branches with a saw chain. A pole saw is an integrated unit comprised of an engine, saw chain, wide bar, pole, and grips (handles) that are designed to be held by two hands during operation. * POWER HEAD The power-producing portion of the unit, comprised of the engine, grips (handiest, throttle control, hottie lockout, and other components.