We have an online account with True Value Hardware (http://www.truevalue.com, use account e-mail riwilson@caltech.edu, password amsterdam).

It is not possible to get tax-exempt ordering from Home Depot, so just pay tax if needed. The Assad lab and the Regehr lab both have extensive collections of exotic tools that we may borrow if we do so politely. The thin cutting wheels for the Dremel tool are Dremel part # 409 or 425. Dremel 425 corresponds to Home Depot #162935. Dremel #409 is available on Amazon.com.