The Incase Envelope Sleeve’s design beautifully complements and protects the streamlined form of your MacBook. A magnetic snap closure further secures your Mac while allowing for easy access. The exterior is wrapped in Woolenex, a premium, ultra-durable polyester-based fabric that has the hand feel of a cotton blend and repels moisture, mildew, and chemicals. It's also resistant to abrasion, stretching, and shrinking.