Female-Female Standoffs

Lyn-Tron's Comprehensive Buyer's Guide to All Things Female-Female Standoffs

Standoffs are used to separate, position or connect components in an assembly. Originally designed for spacing and stacking circuit boards, standoffs are now available in a wide variety of materials, platings, threads, and length combinations for different applications. Threads are compatible with other standard, Off-the-Shelf hardware, with custom threads available upon request. Common customization options include unique threads, custom lengths, and non-standard thread depths. Other changes are often easily incorporated into production.


Standard Female-Female Metric Standoff

Standoffs were developed as electronics evolved and became more complex in the number of components and circuit boards being used. Designers and engineers needed to add strength and rigidity to the assembly. Spacers were first used for this purpose and allowed for a screw to pass through the spacer and board and then being attached with a nut. This worked well when only stacking a few boards and/or doing smaller quantity production. When production volumes increased, standoffs were designed for faster assembly as they reduced the number of fasteners needed and made stacking several boards together more feasible. These same benefits were quickly picked up on by other industries and standoffs are now found in medical devices, aerospace, electronics, industrial designs, consumer goods and many other applications.

Selection Guide

When designing and choosing a Standoff for your next application, it is easiest to think of standoffs as 3 separate sections; the two threaded ends and the main body.  The below guide will help you think through those 3 sections and provide the common information needed for finding the right standoff.

  • Step 1 - Thread Type
    • Standoffs are divided into a few different styles and named after the type of threads on each end.
Female-Female Standoffs

These are also referred to as a Threaded Spacer and come with female threads on both ends of the part. This allows for a screw or male standoff to be installed on either side. In shorter lengths, standoffs will be threaded through the entire part, where longer standoffs are threaded to a minimum thread depth. Female Standoffs can also include a “Swage” end providing a more permanent installation option.

Male-Female Standoffs

These have one end with a male thread and the other end has a female thread. These are excellent for use when stacking circuit boards as each male thread can be installed into the mating part’s female thread. This quickly reduces the number of fasteners needed in the assembly while also reducing installation time.

Male-Male Standoffs

This has male threads on both ends and are used to connect 2 female threaded components. These are also commonly utilized as thread adapters to convert a female thread to a male thread. Male ends can be the same or a different thread for a wider range of applications.

  • Step 2 - Thread Size
    • Standoffs are readily available in all common thread sizes, in both inch and metric series. While most commonly found with each end having the same size thread, different thread sizes are available upon request.

  • Step 3 - Body Length
    • The third part of the standoff once the thread sizes have been determined is the body. As standoffs are commonly used to separate 2 components, the body of the standoff is what will separate the components. As each application will require a unique body length, all standoffs come in a wide range of length options. Parts are machined to a tight tolerance of +/-0.005” (+/-0.13mm) for a secure and consistent fit. Custom lengths and tolerances are available upon request.

Inch Standoffs Standard Lengths Available
1/8" Standoffs 1/8" - 1"
3/16" Standoffs 1/8" - 2"
1/4" Standoffs 1/8" - 10"
5/16" Standoffs 1/8" - 10"
3/8" Standoffs 1/8" - 10"
1/2" Standoffs 1/8" - 10"
5/8" Standoffs 1/8" - 10"
Metric Standoffs Standard Lengths Available
4.5mm Standoffs 3mm - 51mm
6mm Standoffs 3mm - 51mm
8mm Standoffs 3mm - 51mm
10mm Standoffs 3mm - 51mm
13mm Standoffs 3mm - 51mm
  • Step 4 - Outer Diameter (OD)
  • All thread combinations have multiple, standard outside diameters to choose from to give the exact form, fit and function you are looking for.

    • - A Larger OD creates a thicker standoff and is an easy way to add strength and rigidity. The added wall thickness will resist bending or warping during installation, but also adds bearing surface to prevent damage on soft and delicate materials.

    • - Smaller OD’s result in a thin standoff and are perfect when space and weight are the primary concern. Choosing a smaller OD will decrease the footprint of the spacer. This gives more room for other components and reduces part weight. 

  • Step 5 - Profile
    • Hex Standoffs are often selected when installing with wrench or pliers as the “Hex Flats” provide a surface to grip onto during installation. Round and even Square profiles can also be used and provide a clean, distinctive appearance. When using multiple standoffs in the same assembly, some manufacturers will select different profiles on similar parts to provide a visual difference on the assembly line.

  • Step 6 - Material & Plating Options
    • When deciding on a material and plating/finish, there are many properties that can be considered. The most common ones include Corrosion and Rust Resistance, Magnetism, Electrical Conductivity, Strength to Weight Properties, Color, and Cost. Review the chart below to see which standard material has the right properties for your application’s environment.  For an explanation of RoHS, Conflict Minerals, WEEE and REACH visit our Technical section.

Materials Corrosion Resistance Magnetic Electrical Conductor Strength to Weight Color Plates
Stainless Steel High Slightly Yes - Poor Above Average Grey Available
Steel Low Strongly Yes - Poor Average Grey Available
Aluminum Average No Yes - Average Very Above Average Grey Available
Brass High No Yes - Below Average Average Yellow Available
Nylon High No No Average White and can be dyed to other colors No
  • More Questions?
    • Lyn-Tron has been the leading manufacturer of Electronic Hardware for over 50 years! We offer a full line of standard Electronic Hardware, but will manufacture custom sizes and OEM designed hardware to your print. Contact us today with any requests for Electronic Hardware or custom parts manufacturing.