DTA 40137 is a full set of Struts / Shocks. It comes in 4 pieces to fit the 4 corners of a vehicle. DTA Struts / Shocks are manufactured to exceed original equipment standards. It features a nitrogen twin tube design to provide a quick dampening response, and it has a self-adjusting valve system to ensure product performance sensitive to road conditions, providing a smooth controlled driving experience. The use of NOK multi-lip piston seal is designed to effectively seal to prevent external dust and debris from entering in gas & oil. High strength steel rod is micro-polished with double chrome plate. All rod surface finished roughness is less than 0.08um. This results in better corrosion resistance, longer service life and friction reduction. An all weather condition shock absorber, contains oil with excellent temperature-viscosity performance (-45° C to 100° C), reduces the wearing of the internal valve components, providing longer durability. The product is ISO/TS 16949:2002 quality certified with 2 years / 24000 miles limited product warranty.