Lowering springs Z4 ROADSTER 18i/20 mm. Made in highquality silicone steel with High quality Epoxi coating to stand salt and other woundsi/23i/28i/30 mm. Made in highquality silicone steel with High quality Epoxi coating to stand salt and other woundsi lowers 30/25 mm. Made in highquality silicone steel with High quality Epoxi coating to stand salt and other wounds