Coverking Custom Car Cover for Select BMW Z4 Models - Stormproof (2-Tone Gray with Black sides) Made from soft micro-fiber fabric, the material is highly breathable and lightweight yet water resistant, making it ideal for indoor or outdoor use Provides exceptional protection from harmful UV rays and extreme weather such as heavy rain and snow and fabric is untreated and uncoated so it will not fade even after years of intense exposure to the sun Manufactured using unique double-stitching and waxed thread technology as well as the fewest seams possible to reduce leaks and provide greater durability Tailor-made to the exact specifications of your vehicle's year, make, model, and configuration options Neoprene elastic tensioners sewn in the front and rear keep cover in place while the additional security grommets on outdoor covers allow you to utilize an optional lock and cable kit