This Valve Brush features a shank with (2) 1/8” female NPT inlets.  A pipe plug installed in one of the inlets can be removed to connect brushes in a series.   An adjustable precision needle valve controls the flow rate; it has a friction lock to guard against loosening from vibration.  The 1/2"-20 threaded shank can be mounted to a bracket using the plated steel nut and washer.  The bristles are nylon (stainless steel is also available, part no. A2261-SF1BHW).   The total height of the brush is 5 11/16”.
 
The shank is adjustable to accommodate up to 1/2” of bristle wear.  A replacement brush is readily available.