The FSA Compression Plug – 1″ is a precision-engineered replacement for the traditional star nut, designed exclusively for use with carbon steer tubes. This set includes a robust alloy top cap, an expander plug, and a retaining bolt—delivering secure, maintenance-friendly headset pre-load while preserving your frame’s structural integrity. Crafted to fit 1-inch threadless forks only, this compression plug ensures reliable headset compression without the risk of damaging carbon steer tubes through improper assembly. It creates a sleek, integrated appearance while offering secure performance on demanding rides. FSA Compression Plug – 1″ Specs at a Glance Compatibility: 1-inch carbon threadless steer tubes only (not compatible with 1 1/8″) Includes: Alloy top cap, expander plug, and mounting bolt Function: Replaces traditional star nut and top cap, offering safe compression on carbon systems Design Benefits Carbon-Safe Assembly: Avoids use of star nuts which can compromise carbon steer tube integrity—prolonging durability and longevity. Complete Kit: Everything needed—including bolt, cap, and expander—is provided in a single package for easy installation. Precise Fitment: Tailored for 1-inch steerers, ensuring a snug, secure interface and proper headset preload. Final Take The FSA Compression Plug – 1″ is a must for cyclists using carbon forks with 1-inch steerers—providing a safe, elegant, and reliable headset preload solution. Its integrated design simplifies setup and helps maintain the structural health of your carbon steering system.