The Brompton Metro Waterproof L Messenger Bag is designed for the year-round, all-conditions commuter--one's with Bromptons, specifically, as this bag is only intended to be mounted to the Front Carrier Block on a Brompton. The bag measures 16" wide by 11.5" high by 5.5" deep, amounting to a capacity of 20 Liters. The outer shell is constructed of 840D TPU Coated Nylon and is lined with 420D TPU Coated Nylon. Other features include: durable aluminum hardware, YKK zippers, a webbing carry handle, 2 large roll-top rear pockets (also waterproofed), a waterproof zippered front pocket, and an integrated shoulder strap. The main compartment contains a laptop sleeve and a mesh zippered pocket. This bag has a black exterior with an orange inner lining.