The Brompton Borough Tote Bag (S) is a front-mounted bag that's closer in size to a purse or handbag. It measures 11" x 11" x 4.3" and has a capacity of 9 Liters. The bag's exterior is made of 915D Polyester Twill and it's lined with 210D Nylon Lining.  These fabrics are water resistant, however, the bag comes with a hi-vis, waterproof cover if inclement weather strikes. The bag closes at the top with a single zipper and has two external sleeve pockets and an interior zipped pocket. A soft webbing shoulder strap can easily be tucked into the sleeve pockets while the bag is mounted on the bike. As with all the Brompton front-mounted bags, this one requires the front carrier block. This bag is a dark green color, which Brompton calls Olive.