Shields Bilgeflex hose I.D. 3/4" or 19.1mm. Color: Black. Note: Do not attach to thru hull fitting below the water line. Bend Radius 3/4" or 19.1mm. Shields Bilgeflex Hose is a single layer corrugated polyethylene hose. It is resistant to mild chemicals and salt water and there is a clamping cuff every foot. This hose is primarily used for bilge pump discharge. Vac Rating 20. Length 6' or 1.8m.