MilSpec A-Lock Fasteners

 ...are common to BeechCraft / Raytheon airplanes and latches on many cowlings. The design consists of a simple stud, with a pin pressed into the shank. The pin must be pressed in after the stud is inserted through the panel hole and removed from the stud prior to removing the fastener from the panel. Some applications use a flare type grommet in the hole to protect it from wear due to vibration. Unlike other fastener styles, this grommet usually does not require replacement when installing new studs.

MilSpec A-Lock fasteners are made in various sizes and styles. The stud's head diameter determines the stud series. Each stud series is available in either a countersunk (flush) or a round head style. Stud diameters and head styles are indicated by the Base Part Number. Studs come in different Total Lengths which are indicated by the first dash number.

Each stud blank length can have up to ten (10) second dash numbers, or grip sizes. The second dash number indicates the maximum grip range in .010" increments. A-Lock fasteners have the least grip range of any quick release fastener. Therefore, it is important to measure accurately when using them.

Installation Tip:  Pin removal and installation tools for these fasteners are hard to find and very expensive. As an alternative, you can remove an existing A-Lock stud by simply cutting off just enough of the cross pin to remove it from the hole. To install new studs, modify standard Vice Grip pliers by grinding a slot into one jaw. This will provide a relief for when the pin is pressed through the stud. If new grommets are necessary, a grommet flaring tool can be found below, as well as on our main Tools Page.