What's the difference between single-stage, two-stage and three stage snow blowers?  Single stage is a paddle type snow blower.  Two-Stage has one auger on the outside within the shield and one auger in the actual thrower.  Three-Stage snow blowers have two augers in the shield and one auger in the thrower.  Three-Stage snow blowers are better for heavy, thick, frozen snow because it can grind more snow volume.  They all work well.  Single and Two-Stage snow blowers just take a little longer to get the job done.