PlaneSkate's Porter Dollies come in a pair. Placed under each main tire, they allow the aircraft to be moved by hand in any direction (with all 360 degree casters) with very little effort. With restricted hangar space, the Porter Dollies allow you to move the aircraft in any direction allowing you to use every square foot of your hangar efficiently. Designed for 10,000 lb. GW. aircraft and less, these tools were designed at our customers request.