Filtered orifice restrictors build on Air Logic's orifice product line with the additional protection of an integrated filter. Orifices work on the principle of Flow Restriction with the orifice diameter being identified in the part number and by color codes assigned to each orifice size. In addition to orifice diameter, Air Logic controls many smaller factors that have an impact on the total restriction of the orifice. This is why Air Logic's orifices are trusted to provide accurate and reliable flow performance across a variety of different markets. All of the Air Logics products are precision molded, assembled, and tested in America. Filtration immediately upstream of the orifice will protect the orifice in case of system contamination.