The PRO EC Headset boasts lightweight sealed aluminium cups, including a slit crown race for trouble-free and carbon-friendly installation, along with markings to assist in proper cup alignment during the process. COLOR Black   MATERIAL Aluminum   SIZE EC 34 | EC 44   EXTRA INFO Lightweight aluminum cups, sealed cartridge bearings, slit crown race for easyand carbon-safe installation, alignment marks for precise positiong during installation   WEIGHT 124 g