Mishimoto MMCLAMP-35T Stainless Steel Constant Tension T-Bolt Clamp, 3.5, Silver Stainless steel construction resists corrosion Spring loaded for consistent holding power Locking nut keeps clamp from loosening More durable than traditional worm clamps Mishimoto Lifetime Warranty Actual clamping ability: 3.39 inches to 3.7 inches