What is Disinfection in waste water treatment Shock Absorber Type 640 Road. The basic edition of the Wilbers Adjustline mono shock absorber features the same advanced technology as the more complex versions. The only difference is the omission of the compression reservoir, and therefore the ability to adjust high and low speed compression. Despite this, the shock absorber makes no compromises in terms of response behavior or durability. Its radial piston design, wet run operation, and Teflon guided self aligning bearings redefine the quality standard for a mono shock. As usual, the spring preload is continuously adjustable, and rebound damping can be set via an open bleed system in 22 clicks. The shock absorber can also be retrofitted with a variety of Wilbers accessories. Product may vary from picture.