Experience the ultimate harmony between your bicycle's headset and spacers with the Interlok Headset Spacers. Sporting a patented, interlocking design, these spacers bring a unique and secure finishing touch to any Cane Creek headset. They come with a small flange that allows them to nest into each other, ensuring a seamless fit. But that's not all! They also feature a corresponding groove on Cane Creek headset top covers. This tight fit helps eliminate creaking and ensures direct transmission of preload force to the headset bearings below. Let's hear it for smooth rides and American innovation! But wait, there's more! The AER Spacers are a game changer. Ultralight and machined with precision, these Interlok spacers boast weight-saving cutouts. Offering a whopping 33-50% weight savings compared to standard Interlok spacers, the AER Spacers take lightness to a whole new level. So, gear up, lighten the load, and feel the freedom of the open road! Patented, interlocking design Small flange for nesting Corresponding groove for headset top covers Ultralight AER Spacers with weight-saving cutouts 33-50% weight savings with AER Spacers