Clear bra will turn yellow and crack from a few different reasons. First, If a cheaper product that has not been fully tested and perfected will turn yellow and start to crack over time. Extreme autoworks uses only the top quality clear bra and has full warrinties on evey install. Second, The most common way clear bra will turn yellow and crack is from improper care and matinance. If you wax the clear bra it will cause it to fade and crack, however it will take 4 years or more to turn yellow but it will turn yellow over time.