Poulan Pro PR111 21 in. Single-Stage Gas Snow Blower, The PR111 Poulan Pro 179cc Gas Single-Stage Snow Thrower has a working width of 21 in., which is perfect for 2- to 4-car driveways. Single-stage snow throwers use the durable auger to propel the unit forward while gathering in snow then throwing it out through the chute. Controls are large and easy to operate while wearing gloves. Larger 8 in. x 1.75 in. wheels provide better maneuverability in tough conditions.