There are a total of 8 cylinders in the Audi R8 Spider convertible hydraulic system. We upgrade your cylinder(s) by replacing the tiny OEM rod seal with a much larger one made of superior materials, and adding custom caps made of CNC machined stainless steel to accommodate these superior seals. Our seals are not sensitive to water and are resistant to most additives in hydraulic fluid. This results in a much longer service life than the standard OEM cylinders for a fraction of the price. Important: Polished cylinder shafts must be free of rust or scratches from tools for a successful rebuild. If the shaft needs to be replaced, there will be a surcharge for shaft replacement with a hardened stainless steel shaft manufactured by Top Hydraulics. Top Hydraulics can provide replacement hydraulic lines if needed. Top Hydraulics' also rebuilds and upgrades convertible hydraulic pumps, as well as manufacturing our own upgraded hydraulic lines. Owning and driving a convertible with an automatic top is prestigious, convenient and exciting - let Top Hydraulics help you enjoy your beautiful car even more by making your convertible top system truly better than new! Top Hydraulics' standard warranty is 3 years on rebuilds/upgrades of convertible top cylinders and hydraulic pumps, and on new hydraulic hoses.