Dyson Pure and Pure Hot+Cool fans are on sale for $100 off at Amazon

April: It’s cold in the morning and randomly 70 degrees when you leave work, but at least pollen is a dependable constant. 

Air purifiers are a must for those allergies, but switching back and forth from heat to AC is guaranteed to mess with your bill.

HEPA filter fans from Dyson could be the relief you need, and both the Dyson Pure Cool and the Dyson Pure Hot + Cool are $100 off today. 

Both fans rock the notorious bladeless design, and that hollow hole does a lot more than just look really cool. It makes something called Air Multiplier tech possible, circulating 99.97 percent pollutant-free air through room up to 400 square feet. (Dyson says the technology delivers 77 gallons of airflow per second. Air is measured in gallons now.)

Imagine looking across the room and not seeing dust and pet hair floating in there.

The Dyson Pure Cool is the taller, skinnier model and only works as a fan and air purifier. This is a great option for people who are always hot; those who are always cold (raises hand) will appreciate the space heater feature of the Pure Hot + Cool — especially in the summer when everyone else in the house says no, you absolutely may not turn the heat on.

Regularly $399.99 and $499.99, you can save $100 on either model and snag the Pure Cool for $299 and the Pure Hot + Cool for $399.