The Chrome Excursion Rolltop Bag is Chrome's high capacity answer to keeping your possessions dry and protected. Chrome's unique knurled welded construction reduces bulk to an absolute minimum, and contributes to this bag being completely waterproof. And it's backed by Chrome's legendary lifetime warranty, so you know it won't let you down.This bag is constructed out of waterproof 600 denier nylon up top, with an abrasion resistant Hypalon base panel. The panels are bonded by a knurled welded construction, which uses high frequency radio waves to permanently bond the pieces of fabric. This is an essential step for making this bag truly waterproof, and minimizing bulk, which will remove any doubt you may have about storing your computer in the internal 15 laptop sleeve, regardless of the deluge you may face. The rolltop closure expands to carry up to 37 liters of your prized possessions. The straps are Chrome's own super comfortable EVA straps, which work in conjunction with the custom EVA back panel to take the pain out of carrying heavy loads. And the burly tote straps give you a secondary carry option when you want to free up your shoulders. The Chrome Excursion Rolltop Backpack is available in a 37L size, and in the color Black.