SenSen uses OE quality coil spring suppliers for all complete strut assembliers with high standards for quality control and metallurgy. SenSen strut mount assembliers use bearings from a world-class manufacturer with quality awards from companies like Hitachi Vehicle Systems. The quality of oil used in the part is critical to avoid foaming, fade and noise problems. SenSen uses Premium OE Eneos oil that keeps its properties at temeratures of 130c to -40c. If the oil does not maintain its properties with a high tempreature; the shock.strut assembly will fade at high temperatures and cause noisy operation at low temperatures. SenSen uses NOK double lip oil seals. NOK is a Japanese premium quality seal supplier. Limited Lifetime warranty,