Save yourself the trouble, this company is a rip off. They have a small size and a large size and the ones I received were too small. I opened one to try it and it did not fit. I asked about returns and was told that for sanitary reasons they can't accept returns. It would make sense except the things are completely sealed so there is not way to tamper with them. I was offered a discount to purchase another size but after seeing how the ones I received worked, I don't thing any of them would work. Why would I spend more money not knowing if it will fit or not. I blame myself, I should have read the reviews before buying. I don't usually write reviews, but wanted to warn other poor saps who are tempted to order from this company.