1/2" NPT Micro Filter All micro filters supplied with preassembled Automatic Overnight Drain. Porous bronze 40-micron filter element allows less pressure drop and longer cleaning intervals. Safety metal bowl guards or metal bowls available with 1/4, 3/8, 1/2 models. Metal bowls only on 3/4 and 1 models. 3 stage baffle system for exceptional moisture removal. Sintered bronze elements are permanent and cleanable. Lightweight aluminum die-cast housing. Element range 10 or 40 microns exactly matching filter and air flow needs. metal bowls 1020