Rainshower 12 In. Shower Arm With Square Flange GROHE StarLight finish for scratch and tarnish-resistant surfaces for a lifetime of beauty 1/2 in. NPT male threads Can be used with any shower head ExCEPt Rainshower Jumbo (28 783) GROHE StarLight finish for scratch and tarnish-resistant surfaces for a lifetime of beauty. " NPT male threads Can be used with any shower head EXCEPT Rainshower Jumbo