@erik_squires Around $250. I’ve just recently discovered these, and plan on installing one on my condenser.
I also have these on my humidifier, dehumidifier, refrigerator and furnace (i.e., any device I own that has a motor or compressor), even though I rarely ever experience brownouts (you never know though when they might pop up). I like to be proactive (some may call it OCD). This also looks to have one of the lowest *specified* clamping voltages (140 V) I’ve ever seen on a surge protector. Even though I already incorporate a ton of surge protection in my house, and on my video and audio gear, I may even consider adding one of these to the audio and video (non power amp) AC feed for this gear: