ZN400-6B - 3-1/2" NPSM Adjustable 6" Round Strainer (Polished Nickel Bronze Top)Zurn ZN400 6B 3 1 2" NPSM Adjustable 6" Round Strainer (Polished Nickel Bronze Top) Zurn Z400 head assemblies come standard with a shank and variable grid options that allow for versatility to the Z415 drain body. Designed for the Z415 drainage system, these assemblies provide installation and rework savings with Zurn's patented contractor solutions. Features Available in polished bronze and nickel bronze Type S square adjustable, light duty strainer