TR2-6 front spring insulator. Superpro Polyurethane version of 100751 standard thickness. Kit includes 2 insulators. 3 kits required for TR2-4, 2 kits for TR4A-6. Kit SPF1028-5K is a similar insulator, but 5mm thicker that can be used to raise the car both side together or one side only to correct a lean to one side. See below

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