Review on 🏍️ Upgraded Bertoni Motorcycle Goggles: Innovative Photochromic Lens, Interchangeable Arms & Strap, Model 333! Enhance Your Motorbike Experience with Sunsensor Riding Padded Glasses by Eric Miller

If you think your Bertonis won't change in the sun, clean them then put them in the freezer for two hours. Then take them out and place them in DIRECT SUNLIGHT for 15-30 minutes. By then they should be completely dark. From now on they will lighten and darken without any problems depending on the sunlight. If your car/truck windshield has UV protection, your glasses will likely NOT darken while you're in the car. The intensity of the sun's UV rays makes the lenses darker. Hooray!