1byone via Amazon offers its 1byone Safety Driveway Alarm with two Sensors
, model no. O00QH-0518, for $30.99. Coupon code "7PGWBV6W" drops it to $24.99
. Plus, Prime members bag free shipping
. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.49.) That's the lowest total price we could find by $4. The receiver features an AC adapter, high- or low-volume chime or alarm tones, and flashing LED lights. Each waterproof sensor detects people and cars up to 66 feet away and then transmits a wireless signal back to the receiver up to 328 feet away.