Features: Multi-size package,this package contains 4 different sizes, 2mm, 3mm, 5mm, 10mm, small size of spacers headset let you have more precise height adjustment. Material,bicycle headset spacers threadless are made of alloy material with smooth surfaces and delicate workmanship, eco-friendly, durable to use. Lightweight,aluminum headset spacers lightweight and easy to install, resistant to corrosion, more durable than carbon fiber headset spacers, fit most of the bicycles. Size,stem spacers road bike inner diameter 28.6mm,1-1/8inches headset spacers set, compatible with 28.6mm front stem fork of mtb, bmx, mountain bike, road bike. Package include,3 pieces 10mm + 3 pieces 5mm+ 3 pieces 3mm+ 3 pieces 2mm. Specifications: Material:Aluminum Alloy Note: Please allow 1-2cm errors due to manual measurement,plsease make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item Package includes: 12 Pieces Bicycle Headset Spacers