Review on Enerzen O-922D - Digital Ozone Generator - O3 Air Purifier Ionizer Deodorizer Sterilizer with Customizable Settings Ideal for All Room Sizes by Kim Rush

Didn't feel like giving 5 stars for 'small spaces' because I've used this in both small and large spaces and it works great. This ozone generator far exceeded my expectations for odor elimination. We bought a large 5 wheel trailer which the previous owners smoked to the point we could smell it 100 meters away it was that bad. After 4 hours of operation, the smell was gone. I was more than surprised. Hope it holds up over time.