Premium Material our tire covers are made of heavy-duty 210D oxford cloth material. waterproof, great for rainproof snowproofing. High reflective coating is good at sunproof.So it is much more durable in extreme weather. Why use a tire cover ? the tire cover protects the tire from sun damage, corrosion and all types of weather when your vehicle is parked. Keep wheels in good shape and extend your service life. Universal Universal fit 27-29 inch tire diameters (not the rim size). Use on rv, boat trailers, campers, jeeps, trucks and suv. Product details Elasticized band design for a secure fit. the tire is covered on the wheel even on windy days. Easy to install and remove.Come with a waterproof storage bag. Calculate tire diameter For 205/75/15 tire.Calculation formula is 205/10/2.54*75*0.01*2+15=27.1 inch. Just replace the number 205 75 15 with real tire data.you will get the real tire diameter