NAC sells two different rotor protection products, and it's a fair question which one belongs in your kit. They solve overlapping problems but aren't interchangeable — one is built around a wash-day routine, the other around a bike that leaves the house.
Disco Disc Protection Cover: Built for Wash Day
The Disco Disc Protection Cover is a simple, lightweight shield that slips in behind the largest gear at the rear hub before you start cleaning or lubing. Its entire job is to sit there quietly and block degreaser, chain lube, and polish overspray from reaching the rotor while you work on the rest of the bike. It's fast to fit, fast to remove, and it's the product to reach for every single time you wash or lube your bike at home.
Disc Cover Pro: Built for Full Coverage and Transit
Disc Cover Pro does a similar job during maintenance, but it's a more substantial velcro-fastened cover that wraps fully around both the rotor and the calliper — not just the disc itself. That extra coverage matters most in two situations: workshop sessions where you're spraying protectant or polish more broadly around the wheel, and transit, where the covers double as protection against knocks and scratches when the bike rides inside a car boot or back seat. It's sold as a pair, front and rear, specifically because travel and storage are part of its job description.
So Which One Do You Need?
If your main use case is a regular wash-and-lube routine at home, the Disco Disc Protection Cover is the simpler, faster tool for that specific job. If you regularly drive your bike somewhere — a trailhead, a race, a friend's house — or you do more thorough workshop sessions involving polish or frame protectant near the wheels, Disc Cover Pro's fuller coverage earns its keep. Plenty of riders end up owning both: Disco for the quick weekday clean, Disc Cover Pro for the weekend trail trip.
Either way, the underlying logic is the same — a physical barrier is a more reliable fix than trying to clean contamination out after the fact.