I bought this to use on an Aqua Sourcefaucet. smallest adapter is too small, other two are way to large.

Thank you for your interest in Danco products. We apologize for the inconvenience you have experienced. When we designed this product, we tested it on many brands, including AquaSource. It seems there is at least one model in the AquaSource line of faucets that differs from the one we tested on. We're sorry our product did not meet your needs.