4.5" to 4" ID Short Radius - Gloss BlackThis short radius reducing silicone elbow is 4 1 2" ID on one end and 4" ID on the other end. Short radius and short leg means it fits in tight quarters, such as on turbochargers or superchargers. Temp rated to 350F continuous. Five ply reinforced silicone for high strength. We now recommend all silicone elbows be 5 ply or better. Thick 7 32" to 1 4" wall construction. Recommended clamps are 94100 0450 on the small end and 94100 0500 on the big end.