Arc'teryx Bora Hipbelt:
A properly sized hipbelt makes a huge difference on extended forays into the backcountry. These interchangeable Bora Hipbelts come in three sizes. One important note on fitting your Bora Hipbelt: To properly size a hipbelt, load your Bora pack with about 20 lbs. (8 kg.) of gear. You need to place the weight evenly in your pack--not clumped together in a heap at the bottom. Put the pack on and tighten the hipbelt securely around your hips, making sure that your iliac crests are centered top to bottom under the hipbelt. If properly sized, the ends of the hipbelt should extend at least two inches (5 cm.) past your hipbones but not so far that you could ever get them to meet even if you really cinched up the waist belt.
