Dera B01 Trail Running Belt

The B01 running belt is designed to eliminate bounce and chafing with its innovative Dial-Fit System, which tightens evenly around your body so you can fine-tune the fit mid-run without breaking stride.

It includes a co-developed 575ml HydraPak UltraFlask with a locking cap, and the belt can accommodate up to two flasks, allowing you to carry over a liter of fluid alongside your phone, nutrition, and an extra layer. 

Thoughtfully organized front and rear storage keeps your essentials separated yet easily accessible, while a water-resistant stash pocket protects electrolyte tablets, gel wrappers, car keys, or emergency cash. An external zip pocket provides quick access to smaller valuables, and the rear pass-through sleeve securely holds trekking poles or extra layers.

Constructed from one of the most durable fabrics used in running belts, the B01 resists abrasion and punctures while remaining comfortable against the skin. Weighing just 4.2 ounces (size medium), it delivers lightweight performance that virtually disappears on your run.

Sizing

Take your measurement at the midpoint of where you'd like the belt to sit on your body. Note: this is not your pant size.

Measure while wearing whatever you plan to wear with the belt. If you prefer to wear a belt on top of a shirt, measure over your shirt.

If you sit between sizes, size up if you prefer a more relaxed fit, size down for a performance fit.