Thumb Score: +59 Amazon.com has Franklin Sensors 710+ Professional Stud Finder w/ Built-in Bubble Level & Ruler on sale for $39.99. Shipping is free. Thanks maverick2007 Deal Editor's Notes & Price Research: Unlike conventional stud finders which use only 1 or 2 sensors, the Franklin Sensors ProSensor 710 uses 13 sensors simultaneously to detect studs.