These are high-quality vibration dampening feet made by 3M. It uses their Isoloss-SL material Link
Contents include 4 feet with protruding studs and 4 matching stainless-steel nuts.
At first glance these may not seem worth the price but once you work with them you will change your mind. Compared to our standard rubber #4-40 feet it is like comparing hard plastic to something that really lives up to all the qualities that you would want in feet - vibration dampening and good grip.
If you were to take two similar setups, one with these feet and one with standard rubber feet, and tilt them and let them fall the difference is amazing. With these, the setup lands softly and vibration is dampened out very quickly. Compared with standard rubber the standard rubber just seems like plastic.
If you like quality components that just feel good to work with these are for you. Or, if you have sensitive test setups or need to put a setup in a hostile environment these are the way to go.
We use a variant of these with a stud on one end and embedded female thread on the other for mounting backplanes in our rugged cases. This provides an isolation between the two with only the high-quality dampening material in the middle allowing some room for the backplane to move freely relative to the case and for vibrations and shock to be dampened out.
Available in 3 sizes:
- #4-40 - 0.32" high, 0.275" dia feet Drawing
- #8-32 - 0.5" high, 0.4" dia feet Drawing
- 1/4-20 - 0.625" high, 0.615" dia feet Drawing
#4-40 are great for individual modules or small backplanes. #8-32 are ideal for mid-sized backplanes (our 6"x6" backplane works perfect with them). The 1/4-20 feet are much larger and work great with our largest 12"x12" backplane.