Plumber

The plumber is the owner of Stern Lecture Plumbing and a former Stonecutter.

History
When there was a leak in the basement, the Simpsons called in Stern Lecture Plumbing. The plumber came and told them that he had to order a new part and it could take weeks. He comes back and tells them that he hasn't ordered the part yet before Homer does the secret Stonecutters handshake with him and reveals that he too is a Stonecutter. He then fixes the leak with one turn of a wrench.