Optimised response characteristics and large reserves generate very secure ground grip combined with high levels of comfort. These suspension struts permit infinite adjustment of the spring pre-tensioning and a 22-position traction level adjustment of the suspension. The classic version complies with what is "normal" but has a black spring instead of a blue one. Approval: With TüV parts approval certificate. As an option, the suspension struts can also be ordered at extra cost with height adjustment (629) and / or hydraulic spring pre-tensioning (625). Repairs and maintenance are possible via Wilbers Products.