Oiosen Official via Amazon offers its Oiosen Plug-In Ultrasonic Pest Repeller with Night Light 2-Pack for $15.99 $14.99. Coupon code "5F7BGF9F" cuts that to $9.59 $8.99. Plus, Prime members receive free shipping. That's $6 off and the lowest price we could find. Each has an effective area of 800 to 1,300 square feet.

A 4-Pack is also available for $25.99 before coupon, $15.59 after. With free shipping, that's $10 off and the lowest price we could find. Both deals end July 20.