Bicycle headset spacers designed to improve fit, comfort, and control for your bike Key benefits Precise height adjustment: Available in 2 mm, 3 mm, 5 mm and 10 mm sizes to fine-tune handlebar height and reach for a more comfortable riding position. Lightweight and durable: Crafted from high-quality aluminium alloy for corrosion resistance and low weight, so you gain stiffness without adding bulk. Better handling and stability: Small changes in headset stack height can reduce strain and improve control on road, trail and daily rides. Easy to install: Slide onto the steerer tube under the stem for quick, tool-minimal adjustments or stack multiples for incremental changes. Features and compatibility Material: High-quality aluminium alloy for long-term durability and resistance to rust. Sizes: 2 mm, 3 mm, 5 mm, 10 mm — mix and match to achieve the exact stack height you need. Compatibility: Designed for common threadless headset systems and suitable for road bikes, mountain bikes, commuter bikes and hybrids. Function: Precise headset spacing to adjust stem height, improve fit and tune handling without cutting the steerer tube. Practical use scenarios Daily commuting: Raise or lower the stem by a few millimetres to reduce neck and back strain during your daily ride. Weekend road rides: Fine-tune cockpit position for better aerodynamics or comfort over longer distances. Trail and mountain biking: Adjust reach and handling responsiveness to match trail conditions or to accommodate different rider styles and suspension setups. Why you need these spacers Simple, low-cost way to dial in fit and handling without permanent changes to your bike. Compatible with multiple bike types and easy to stack for precise, incremental adjustments. Built from aluminium alloy for a balance of stiffness, low weight and corrosion resistance. What's included Headset spacers in the available thicknesses (2 mm, 3 mm, 5 mm, 10 mm). Use them individually or combined to achieve your desired handlebar height and control.