You knew it was coming, and brace yourself for more, as 12mm thru-axles become more ubiquitous for all bikes. Changing times and innovation demands new tools and technology to get the job done. Focus Bikes developed Rapid Axle Technology (RAT) for fast, precise thru-axle installation. Butter, always seeking innovation, jumped into adapting their fantastic b2 Chain Keeper into the b2 RAT Chain Keeper by modifying the axle design and adding the T-end required to lock into the RAT dropout receiver. If you appreciate high quality/purpose built tools and work on bikes all day long we see a b2 in your near future. And if you a cyclist with a RAT equipped bike or another licensing brand, you will want the best chain keeper every made available for your home, travel, and event needs.

As you would expect from any Butter tool, the quality is top shelf. Pure precision machining from solid 6000 series alloy billet makes this a lifetime purchase. In the simplicity is profound department, the b2 is remarkably easy to secure onto your bike and operate. Simply insert the leading guide into the dropout and twist the outer knob to secure to the frame. The proprietary Dog Ear Technology found on the b2 actually duplicates some of what the RAT requires, except with a t-end and slot that locks the b2 RAT into position to prevent rotation during use. By solving the issues related to cleaning and maintaining a RAT equipped 12mmm thru-axle drop out frame, it's apparent to us that Butter Studios has captured lightning in a bottle. The b2 RAT is a must for any true mechanic's tool box.