Stems

FSA's K-Force OS-99 CSI is 3-D forged and CNC machined from AL2014 before a uni-directional (UD) carbon weave skin is applied through the Carbon Structural Integration (CSI) process. To further reduce weight the OS-99 uses a 4-bolt sculpted AL2014 alloy/carbon faceplate and titanium hardware. CSI is a process that permanently bonds carbon to alloy, to create a true hybrid product, with many of the benefits of aluminum and carbon. - Stack Height: 41mm - Weight: 126g (100mm)

At just 113g for a 100mm extension, the Energy stem represents cutting-edge aluminum construction. The shape is 3D-forged from 2014 aluminum for great strength, with the final refinements carried out by CNC machining. Titanium bolts complete the package. - Semi Integrated Cable routing (SCR) - 3D-Forged and CNC-machined from AL2014 - 4-bolt sculpted SL faceplate