im not sure, but this is wat they say about them:
Big diameter piston rods- 14MM diameter for shocks and 22MM for struts.
Big diameter pistons- 40MM diameter
Separate compression and rebound damping rates control.
Unlimited low speed and high speed damping rates available through unlimited shims: stacks.
Superior hydraulic and dust scraper seals that can withstand pressures in excess of 400 bars.
Maximum rigidity through large bearing supports and overlap design.
High quality low friction hydraulic oil used with consistent and stable viscosity over wide temperature range.
Chrome piston rods are hardened and precision ground to exact dimensions.
Fully serviceable designs for all re-valuing, re-gas, and seals replacement.
All eye attachments are molded silent blocks instead of rubber bushes.
Dust covers are 100% natural rubber for maximum flexibility and durability.
Strut is designed with an insert for the shock working body with no welding on the tube at all. This creates a perfect tube with no distortions. All welding is carried out on the outer tube housing.