About Dzus Fasteners

What are Dzus Fasterners?

Dzus Fasteners are made of heat-treated and cadmium plated nickle steel*, and consist of a grommet, spring, and stud, the grommets being composed of aluminum. They are used in convers, plates, cowlings, and similar units, which require quick removal and replacement. When they are broken of otherwise damaged they much be replaced. Replacement of the light-duty type is simple. The heavy duty type required two additional steps, as the retaining grommet must also be replaced.

[*Modern manufactured Dzus type hardware is now often zinc plated.]

Who invented Dzus Fasteners?

William Dzus invented the Dzus "Quarter Turn Fastener" in the 1930's. Originally designed to fit aircraft, the fasteners have found other uses in heavy machinery, race cars and other personal vehicles.

How Dzus Fasteners are identified:

The following designation system is used to identify various shapes of Dzus fasteners.

[TYPE A] has and oval head.

[F and FA] have flush heads , [FA] having a round edge in addition of being flush.

Type [HF] has a hexagonal head.

If the letter [J] is added, as in [AJ] and [FJ], it indicates that the fastener has a longer undercut below the head than types [A] and [F].

If the letter [O] follows the preceding symbols, as [AO], for example, it designated a fastener with no undercut.

The letter [W] indicates the body diameter of the fastener is in sixteenths of and inch.

The number following the dash gives the length in hundredths of and inch.

Spring designations indicate if the spring is standard by the use of the letter [S], followed by a number indicating the size of the fasterner with which is used. This is followed by a dash and a number giving the height of the spring. In example, S3-200 is a standard spring, used with a No. [3] fastener, and is .0200 inches high.

Standard Grommets are designated in the same way as springs, except that their designations are proceeded by either a [GA] or [GF], indicating their use with [F] or [A] fasteners.

For example:

GA6.5-375 indicated a grommet to be used with a type A or AJ, 6.5 fasterner with and overall length of .375 inches.

Dzus Hardware Visual reference

The following images represent thy typical Dzus hardware types. For more information on special Dzus hardware, please checkout the DZUS Quarter Turn Self Locking Fasteners Cataloge - 1944.

Type A Stud