Finish Line Shock Oil- Premium suspension fluid formulated specifically for all oil damped bicycle forks. 100% compatible with ALL suspension designs and seals. A semi-synthetic oil formulation that has become the top choice of professionals worldwide. Will not thicken or thin due to changes in temperature. Low foam technology delivers consistent and predictable damping in all riding conditions. Race proven to deliver superior performance in all suspension systems. A super high viscosity index of over 235 provides consistent damping through the longest and most extreme of riding conditions. 16oz bottles available in 5 different oil weights: 2.5wt, 5wt, 7.5wt, 10wt, 15wt. Customizing fork performance with oil fill and weight choice: You can speed up or slow down your forks compression and rebound characteristics by changing the oil viscosity. 2.5wt is lighter/thinner/faster. 15wt is heavier/thicker/slower. If your lightweight/smaller, go thinner – if you’re bigger/heavier, go thicker. Plus, you can change the oil height/fill volume in your fork to make the spring rate more linear/equal or progressive/increasing as it comes to the end of the compression stroke/travel.