The FootFitter Set of 6 metal Additional Corn Pieces fits only in the FootFitter Premium line of shoe stretchers. Simply insert a corn piece into the spot where you need extra pressure relief. This item ONLY fits the following items: FootFitter Premium Professional 2-Way Deluxe FootFitter Professional 2-Way Stretcher FootFitter Premium Professional One Way Shoe Stretcher FootFitter Premium Professional Boot Stretcher FootFitter Premium 3"-6" High Heel Shoe Stretcher Aluminum Shoe Stretcher