The ISO AB is specifically for Boost disc spacing forks with 110x15mm "Boost" or 110x20mm "Boost" axles.

Using the larger diameter hubshell bearing the ISO AB is designed to tackle rough terrain and aggressive riding such as downhill and enduro. In an evolving landscape of axle specifications, we are confident that the Boost disc location is here to stay. With the ISO AB hub your wheel will be future proof and ready to convert to the new 110x20mm axle with a simple insert swap, should that spec expand beyond downhill forks in the coming years.

Learn how Chris King developed the BOOST AB hub here.
Chris King ISO AB front hubs are designed as precision mountain tools. We use one-piece axles to provide a stiff hub with rail accurate steering, transferring every minute adjustment you make to the trail. To thwart mud, water, and contaminants as you power through rough trails, ISO hubs have heavy-duty bearing seals and snaprings, that provide superior protection with ultra low drag.

Our bearings, available in steel and ceramic, have heat-treated, surgical grade steel races that are machined simultaneously, with tools of equal wear to ensure perfectly matched inner and outer races. The quality and speed of our bearings is what sets us apart from the competition and they are what you will feel and notice on every single ride. As Chris King bearing tracks burnish they get faster with age and all our hubs and bearings are fully serviceable for years upon years of demanding use.