A skid-loader, skid-steer loader, or skid-steer is a small, engine powered, rigid framed machine with lift arms used to attach a wide variety of labor saving tools or attachments. These are typically 4 wheeled vehicles with locking driving mechanisms making for synchronized movement on each side. This enables the machine to "skid" or be dragged by one side of the wheels over the over, making for a turning radius that is almost unmatched in "tight" situations. The conventional bucket of many skid loaders can be replaced with a variety of specialized buckets or attachments, many powered by the loaders' hydraulic system. These include backhoe, hydraulic breaker, pallet forks, angle broom, sweeper, auger, mower, snow blower, stump grinder, tree spade, trencher, wood chipper machine, etc.