Abrasion: The mechanical wearing of a surface from contact with other object.
Aggregate Working Load Limit: The summation of the Working Load Limit (WLL) of all tie downs used to secure an article of cargo.
Anchor Point: The location to which a tie down is attached to a vehicle or article of cargo. If the anchor point is inadequate to support the force of the tie down system, then the load rating of the tie down will be limited to the strength of the anchor point.
Breaking Strength: The tensile load in pounds or kilograms at which any part of the securement assembly fails.
Cargo: All articles or material carried by a vehicle, including those used in operation of the vehicle.
Design Factor: The ratio of the breaking strength to the Working Load Limit (WLL).
Direct Tie Down: A tie down that is attached directly to the cargo.
Elongation: The measurement of stretch at a specifically applied load, expressed as a percentage of the original length.
Fabrication Efficiency: The synthetic web tie down assembly break strength, as a percentage of the webbing strength prior to fabrication.
Indirect Tie Down: A tie down which passes over the cargo and is secured to the vehicle at both ends. Tension in the tie down increases the pressure of an article or stack of articles on the deck of the vehicle.
Keeper: A device used on a hook to prevent the hook from inadvertently releasing.
Length: The distance between extreme end bearing points of the synthetic web tie down assembly, including the fittings.
Lever Load Binder: A chain binder incorporating an overcenter locking action.
MVW: Maximum Vehicle Weight; the maximum weight of the vehicle being recovered, including cargo load, for which the strap is intended for use.
Proof Load Test: A non-destructive load test to some multiple of the working load limit.
Selvage: The woven or knitted edge of synthetic webbing.
Sew/Stitch Pattern: The pattern of the stitches used to sew the webbing together.
Shoring Bar: A structural bar placed transversely between the walls of a vehicle to prevent cargo from tipping or shifting.
Ultimate Test: A load test of a securement assembly tested to failure.
Warp: A longitudinal load bearing yarn in webbing.
Winch: A device for tensioning a webbing or wire rope tie down that is fitted with means to lock the initial tension.
Working Load Limit (WLL): The maximum load a component or assembly should be subjected to during routine use.