Factory-Fit Black Silicone Boot Kit by Mishimoto. Includes: 4 Silicone Boots with DuraCore� Technology, 8 Constant-Tension T-Bolt Clamps, Mishimoto Lifetime Warranty. Inner Diameters: 2 x 2.71in, 2.95in, 3.375in. Outer Diameters: 2 x 3.10in, 3.35in, 3.75in. Mishimoto is proud to release a direct-fit silicone boot kit with DuraCore� technology designed specifically for your car. Mishimoto DuraCore� technology is the synthetic material that comprises the innermost layer of all Mishimoto silicone diesel boots.