One of the coolest things about Yeti's newest bikes, like the ASR5, 575, Big Top, and SB 66, is that they give you the adaptability to tailor the rear axle configuration. You could sling in a standard quick release rear wheel and be off down the trail. Or you can run with a 12x142mm thru axle, Yeti offers this optional Shimano style 12x142mm Chip Kit. The kit is comprised of four pieces of CNC machined alloy hardware that replace the existing dropout chips on your bike. You'll get new fasteners as well. Simply remove the old parts and bolt up the new stuff. You'll be done in less than ten minutes and ready for a ride. The beauty of the 12x142 axle system is that it will make your bike stiffer and it will be more precise through hard corners. Another benefit of the Yeti 12mm Chip Kit is that the 12x142mm system is quicker and easier to get the wheel pulled into place and it's stronger than other thru axle systems. It fits the ASR5, ASR5 Carbon, 575, Big Top, and SB 66. It's designed to be used in conjunction with a Shimano XTR 988 12x142mm thru axle. Please Note: This kit is not compatible with DT Swiss or Syntace X 12 style 12x142mm thru axles.