Sierra Shields Nautiflex Corrugated Silicone Exhaust Hose 4 The Nautiflex Corrugated Silicone Exhaust 4 Hose two ply construction, has wire captured between fabric plies. The hose features a blue silicone tube and cover with a smooth finish for easy cleaning. It also features wire reinforced that will not collapse under suction or in a bend. The corrugated cover allows the hose to bend for easy installation. Specifications I.D. 4 or 102mm O.D. 4 4964 or 121mm Wt. C 255 Bend Radius 4 x I.D. Appli