I sent in 3 different types of shoes. A pair of steel toed work shoes, tennis shoes, and a soft-soled shoe. They all came back with sturdy lifts put in and I began to wear the work boots. I wore them for 4 days and the lift came loose, due to the manner in which I walk. I emailed the company and the boot sole was fixed for free. I have worn the tennis shoes since then, and they are holding up beautifully. It is difficult for me to find a lift that will hold up to my kind of wear and tear. I've met my match, and will definitely be getting more shoes in the future.