I bought this, and I am using it while doing PTs right now. completely silent, and it is able to stand like a tripod so the the dial actually faces you, not flat on the table. just set to 5 every time, so you have 35 min left till it get to 12.

http://www.amazon.com/gp/product/B000GAYQU4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1