StemCap's patented two-piece custom StemCaps System consists of a CNC machined aluminum StemCap Base and an injection molded durable plastic snap-on Stem Cap Cover. The whole system weighs just 7.06 grams, lighter than even your standard headset cap. Clean and simple, with infinite customization options. They're so easy to change out, you can have a different one for every day of the week! Classic Mellow Johnny's designs snap onto the Stem Cap Base (sold separately) add a bit a flair to your rig. Easily swappable to suit your mood. Pick up the StemCap Base