This product seems to be a good way to get extra air ventilation into your Sidi shoes. They're also necessary, because without them, the Sidi shoes would be worn out very quickly. I just wish that these products were a lot cheaper. At over $20 for some tiny pieces of plastic, it seems to be way overpriced. I guess all Sidi products are like that. Take their Sidi Vent Wired shoes that are about $500 per pair.