The Paint Brush Cover is made of a clear, hard, durable plastic, to ensure that the bristles are protected no matter how badly your brush gets tossed around. We utilized a clear plastic to allow users to see not only what size brush you are storing, but also if you have stored a wet brush, full of paint, or a dry brush. There"s no guess work involved.The unique design of the cover allows for easy storage. Simply put it in your tool box, bucket or just throw it on your work bench. We highly recommend "spinning" your brush dry (either by hand or mechanical spinner) to ensure optimal shape. This also prevents your brush from getting moldy. See our Brush Care page for tips on properly cleaning and storing your brush.One of the best features of the Paint Brush Cover is it"s ability to create an Airtight seal during usage. If a break is needed, such as lunch, simply place the brush in the cover and close the lid until the locking mechanism is secured. When you return from your break, simply open the cover, take out your brush and continue on like you never stopped. It"s as easy as that. While we do not recommend it, tests have shown that after leaving your brush, dipped in wet paint, for weeks, it will be as if you had just put it in the cover 5 minutes ago. This will save you valuable of time by not having to wash your brush as often.The Paint Brush Cover is also "one size fits most". With our unique foam seal around the handle, the Paint Brush Cover can fit a 1" brush just as snug as it can fit a 3" brush. This solves the problem of having to buy different size covers for different size brushes (Larger size covers Coming Soon). You can"t get much more convenient then that!Did we also mention that it"s good for the environment? It not only reduces the amount of paint you wash down the drain every time you clean your brush, it also significantly reduces the amount of brushes you throw away each year.