Boston Cuir W Mules & clogs Brown available in size 2.5|3.5|4|5|5.5|6.5|7.5 Women's Birkenstock leather mule with round toe and gum sole. The Boston features the authentic anatomical cork and latex Birkenstock sole that guarantees unbeatable stability and comfort. This pretty closed-toe version, with its creative asymmetric front and antique khaki colouring, simply oozes comfort.