Flat Shank Brushes are used to apply lubricant to chains and other moving surfaces.  The whisking action of the bristles evenly distributes the fluid as it reaches the contact surface.  Brushes can also help prevent dirt build up. 

This horizontally mounted flat brush has an aluminum holder with (2) 9/32" x 5/8" slots on the mounting bracket, and a 1/8" female NPT inlet to attach directly to a supply line.  The drip tube ensures that liquid flows to the brush in the horizontal position. The bristles are nylon (stainless steel is also available, see part no. A2260-SF1).  A replacement brush that slides into the holder is readily available.

The total length of this flat brush with horizontal drip tube is 3 1/2".