− Decrease quantity for Tubing Couplers, Straight, Silicone, Black, 4.00 in. Inlet/Outlet Diameter, 2.00 in. Length, Each Quantity + Increase quantity for Tubing Couplers, Straight, Silicone, Black, 4.00 in. Inlet/Outlet Diameter, 2.00 in. Length, Each Add to cart