The Wolf Tooth Ultralight Stem Cap with Integrated Spacer brings a unique style to your bike whilst remaining ultra lightweight. This Ultralight and ultra-sleek stem cap integrates a 5mm, 10mm or 15mm headset spacer with your stem cap in finely machined piece. Why have extra steerer tube requiring spacers on top of your stem you ask? Well, many carbon steerers require that the steer tube extend above the stem. Also, riders may want the flexibility to move handlebar height up and down for different types of riding or for bike re-sale. Wolf Tooth Ultralight Stem Cap with Integrated Spacer Features 1 1/8 top (straight 1 1/8 or 1 1/2 to 1 1/8 taper) steerer tubes only 5mm, 10mm, and 15mm internal cylinder wall heights Light-weight and durable Wolf Tooth Ultralight Stem Cap with Integrated Spacer Compatibility 1 1/8 top (straight 1 1/8 or 1 1/2 to 1 1/8 taper) steerer tubes only Wolf Tooth Ultralight Stem Cap with Integrated Spacer Specifications Weight (cap + bolt): 5mm - 12g, 10mm - 14g, 15mm - 16g Material:  6061-T6 aluminum Included: Black Aluminum bolt Made in the USA