This was never used - I put it on but the wife like the smoked one better. It was on for less than an hour. This one really adds a lot more light in the cer. The clear is perfect for any trailer that needs more light like an enclosed motorcycle trailer or a dark RV. It fits the standard 14 x 14 vent openings. I paid $50 for this on Amazon.Fan-Tastic Vent Vent Lid, Clear, PolycarbonateModel 1020...