The Boston mule is a classic Birkenstock model, but in an exceptionally luxurious version with a shaft of high-quality smooth leather. Thanks to the integrated belt with a sturdy metal buckle the mule can be individually adjusted to the foot. The anatomically shaped cork footbed coated with suede contributes to an ultimate comfort. The mules have a special outsole so the risk of slipping is quite small. The outsole consists of two components: an oil and grease resistant non-slip rubber outsole and cushioning midsole for lightweight, flexible EVA material. The Boston black leather with anti-slip sole is available in the 'normal' width.