Thule's approach with its computer-accessory line seems to be to embrace the company's design history: The Sleeve's exterior is made of rigid, waterproof, high-density polyurethane with an embossed design that makes the case look like something you'd attach to your car's roof rack. The look won't be for everyone, but I found it to be a refreshing change from all the simple-black and overly-artsy designs out there. The Sleeve's zipper is water resistant with large, easy-to-grab pulls, and the inside of the sleeve is lined with polyester fiber. There's also an elastic strap inside that holds your laptop in place when you open the case.

I tested the 13" Protection Sleeve with a 13-inch Unibody MacBook. The laptop fit great inside, barely moving when I shook the Sleeve. You can even use your laptop without removing it from the case if you'd like a bit of in-use protection--just unzip the Sleeve, open your MacBook, and get to work. However, there's one limitation here: To keep the Sleeve's lid from flopping back when you open it, Thule has added an elastic strap to each side. These straps keep the lid from opening much more than 90 degrees. You can stretch the elastic a bit to extend that angle, but unless your MacBook's screen has a strong hinge, it won't be able to hold the Sleeve's lid open much past that 90-degree limit.

At 13.6 inches wide, 9.8 inches deep, and 1.6 inches thick, and weighing 13 ounces, the 13" Protection Sleeve adds a bit of bulk to your MacBook or MacBook Pro, but it's solid, protective bulk. For storing your MacBook inside another bag or suitcase, or for some extra protection while carrying your laptop by itself, the 13" Protection Sleeve is a solid option, provided you like the cargo-carrier design.