Milton 1110 3/8" NPT Metal Piggyback Filter Regulator. 3/8" NPT piggyback duo has the features of the standard regulator, plus the space saving convenience of a combined filter. This piggyback filter regulator comes with a 6 ounce metal bowl and a 40 micron filter. With an automatic overnight drain and relieving regulator, this duo offers a non-rising adjustment and a 3 position knob to lock, adjust or remove. Has a maximum pressure of 200 PSI and 80 SCFM.