The new Better Boost Adapter Kits allow you to keep your existing 15x100mm front wheel as you upgrade to a new Boost 15x110mm fork.
There are other conversion kits on the market, but ours is the best. One competing kit consists of two loose 5mm axle spacers that are a pain to install and are easily lost during wheel removal. Another provides you with just one endcap and requires that you re-dish your wheel to re-center it in your fork. The Better Boost Adapter Kit consists of two precisely machined end caps and a brake spacer (and requisite bolts), and it requires NO DISHING of the wheel.
Allows for mounting of ISCG-05 to a frame without ISCG tabs. Mounts behind the BB shell. Only compatible to be mounted on frames with BSA BB shell. Problematic on some carbon frames.