[HWYSTR455]

Spray 9, or some other marine surface cleaner. It's made specifically for that, and works great. You can get Spray 9 at Walmart, or you can go to a marine or RV supply place.

https://www.spraynine.com/

Quick search found some other marine cleaners:

Best Boat Vinyl Cleaner Reviews of 2019
1. Meguiar’s M5716SP Marine Cleaner
2. 3M Marine Vinyl Cleaner
3. Spray Nine Marine Cleaner
4. 303 Products Boat Cleaning Spray
5. Star Brite Vinyl Cleaner, Polish and Protectant
6. Boat Bling Vinyl and Leather Cleaner
7. Aero Cosmetics Interior Cleaner
8. 3M Marine Vinyl Cleaner and Restorer
9. BioKleen Multipurpose Vinyl Cleaner
10. Star Brite Mold & Mildew Stain Remover

https://www.marinetalk.com/best-boat-vinyl-cleaners/

Spray on, use a hog hair or soft bristle brush for tough spots, wipe off.

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