B8 5125 Series Driver or Passenger Side Monotube Smooth Body Shock Absorber (33-230337) by Bilstein. Quantity: 1 per Pack. The 5125 Series offers Bilstein technology for custom lifted applications. 5125 Series shocks feature Bilstein s superior single tube high gas pressure design for the upmost in consistent fade-free performance and long life. Gas Pressure Technology. Over time the mono-tube gas pressure technology developed by BILSTEIN has established itself as a standard in automotive construction. This technology involves keeping the oil in the absorber under pressure which prevents it from foaming when temperatures and loads are increasing. As a result full damping power is retained even when the system is placed under extreme stress a feature that can be observed in the self-lowering piston. Mono-tube Upside-Down Technology. The original and best: The original mono-tube gas pressure shock absorbers bore the BILSTEIN name and we?re still responsible for producing the best th This product ships in approximately 1 days