These things are very effective at making a slightly tight pair of shoes more comfortable. The fact that this item comes as two stretchers rather than only one makes it a very practical buy. Put them in a pair of shoes and leave them overnight or for a week and when you wear those shoes again, they could be a quarter size larger, depending on the type and construction of the shoes. I'm very happy with mine and have used them on at least 3 different pairs of shoes. Good for taking a pair of shoes I used to have to wear only thin socks with into shoes I can now wear thicker socks with.