Home Depot offers the Square D Home Electronics Protective Device, model no. HEPD80, for $75. Coupon code "HDHOLIDAY" cuts it to $70. With free shipping, that's the lowest total price we could find by $46 (outside of the price below), although we saw it for $4 less in April. This whole-house surge protector features a 80,000-amp surge current rating. Coupon ends December 3.
A close price: Amazon offers it for $75 with free shipping.