This Cane Creek 40 headset is designed for tapered steerer tubes. The top is standard 1-1/8", while the bottom is 1-1.5" The sleek black color and sturdy construction of this headset by Cane Creek make it a reliable and stylish addition to any bike. With model number BAA0533K, this headset is made to fit perfectly and securely onto your bike. The package includes one headset with top cap and top cap bolt. Sealed cartridge bearings. Cups are alloy construction. NEW in the package. Buyer is responsible for proper installation. When in doubt, take it to your local bike shop to have the cups pressed in and the crown race pressed on. Thanks for looking!