On Ohio registered vehicles, window tint must allow 50% light transmittance on the rear and side windows, and 70% transmittance on the windshield. In other words, the tint cannot be darker than 50% on the side and back, and 30% on the windshield. Remember, auto glass is slightly tinted from the factory, and will make the tint you apply to your windows darker than advertised by the tint manufacturer. Additionally, no reflectorized material is permitted on any part of the windows and decals are prohibited on a the rear windows and below the AS/1 line on the front windshield, except a State of Ohio Vehicle Inspection Sticker