The Cyrano R1 Stem is designed with Fizik's Spine Concept technology to create a cockpit that works together with the saddle to deliver you the perfect fit based on your flexibility. The Cyrano R1 is built tough, using a 7075 series Aluminum Ergal and Aluminum Anticorodal, which offers a tensile strength of 20 tons per square inch. Two Allen screws secure the stem to the steerer, while four Allen screws on the faceplate connect the stem to the handlebars. The Cyrano R1 fits handlebars with a 31. 8mm diameter.