Absolute Filtration Rating: |
The diameter, usually in microns, of the largest solid particle which a specified filter media will pass. |

Collapse Pressure: |
The maximum differential in pressure between two points in a fluid system usually as it relates to filtration. Expressed as ∆ (Delta P) between a housing inlet and housing outlet. This is important when it comes to proper filter maintenance. |

Fluid Compatibility: |
The suitability of using the materials of a filter assembly, filter element, or seal in conjunction with a specified fluid. |

Mean Flow Pore Size: |
Indicates that half the flow passes through openings of equal or smaller size and the rest flows through openings of larger sizes. |

Mesh Rating: |
Indicates the number of openings in wire cloth per linear inch. |

Micron Rating: |
A micron is equal to one millionth of a meter or .000039 (39 millionths of an inch). Expressed in convenient terms, 25 micron is equal to one thousandth of an inch (.0001). |

Nominal Filtration Rating |
An arbitrary micron value established by a filter manufacturer as a realtive indication of average filtration capability. Based on Mean Flow Pore size. |

PSI: |
Pounds per square inch. As it relates to filtration, it means the maximum operating pressure that a filter is capable of. |

Rated Flow: |
The optimum flow rate for which a filter is designed. |

SUS: |
Saybolt Universal Seconds. A measure of viscosity. The time in seconds for 60 cubic centimeters (CC) of fluid to flow through a standard orifice at a specific temperature. |

Viscosity: |
A Measure of the internal friction or the resistance of a fluid to flow. The standard unit of measure is SUS or Centipoises. |