FSA OS-99 CSI Stem

Product Code FSS175-0320B
Other products by FSA
  Options Price RRP In
80mm / Black $309.00 $339.00
90mm Black / Black $309.00 $339.00
100mm Black / Black $309.00 $339.00
110mm Black / Black $309.00 $339.00
120mm Black / Black $309.00 $339.00
130mm Black / Black $309.00 $339.00
Price may differ in our Retail store.

  • In-store: Expect delivery in 2-3 days.
  • With Supplier: Expect delivery in 4-7 days.


The K-Force OS-99 CSI is 3-D forged and CNC machined from AL2014 before a uni-directional (UD) carbon weave skin 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 aluminium and carbon.

Key Features
  • 3D forged and CNC machined from AL2014
  • UD carbon weave skin applied through CSI process
  • 41mm fork clamp stack height
  • Finish UD carbon finish
  • Weight: 126g (100mm)
  • Sizes:± 6° x L80, 90, 100, 110, 120, 130mm