If you're like me who can't stand black scuffed-up leather and faded external sunroof seal in your cars, try leather shoe dye. It's waterproof and comes in a small bottle with a foam top applicator. It comes in other colors other than black, but limited. Just dab it on the area and let it soak in where it is scuffed, and wipe excess off to blend. It dries to a waterproof and permanent finish. Then use your normal leather conditioner for a satin finish blending. To the faded seal, just dab it on after taking it off the car, and you'll have a brand-new looking seal.