My Left foot has always been larger than my right. I always dealt with one shoe being a little tight and the other a little loose till now. My new job requires me to be on my feet all day and I go through shoes pretty quick. I needed to get better fitting shoes right out of the box. I was able to take a new shoe out of the box and saturate it with shoe stretcher then use this to widen the shoe. Now they fit perfect and no break in blisters. The Plastic inserts help stretch the right area for the perfect fit every time. My only regret is I didn't buy one sooner. Worth every penny IMO.