 One user wrote, the Thunderstorm does what it claims. It definitely is effective on my husband's allergies, sneezing, runny nose, and coughing. The Thunderstorm is a small device you can hold in your hand, plug into your electrical outlet, or into your car by USB cable to purify the air. And right now, you can get two Thunderstorm air purifiers for the price of one by going to EdenPureDeals.com and using code GRACEBOGO.