Thumb Score: +15 Amazon [amazon.com] has Klein Tools Non-Contact Low Voltage Test Pen + GFCI Outlet Tester for $19.98. Shipping is free with Prime or on $35+ orders. Price $6.99 lower (26% savings) than the list price of $26.97 *Deal history:[list][*]Frontpage Deal at $20 with 67 Deal Score and 13 comments.