The Smith Hard Goggle case is a solid case designed to protect the expensive goggles you have just bought and keep them and any spare lens's safe and sound. It fits most makes of goggles but the very large lens goggles may be tight. We have tried the I/O and I/OX without any problem for fitment but the spare lens's are very tight for the I/OX size lens. There is a mesh bottom to the case to allow moisture to drain out and not build up in the lens's. There are also felt sleeves to hold the lens's there in reserve and for travel.