Fox 3.0", 3.5", 4.0", 4.4" Smoothie Shock Bottom Eyelet 2.045" Top Edge To Center Uses 3/4" Uniball

It's important to realize that anything 2.5" or greater, regardless of shaft diameter, all have 7/8" thread on the bottom. So for example, if you have a 7/8" shaft, 1" shaft, 1-1/8" shaft or 1-5/8" shaft, they all have 7/8" thread on the bottom.

A common question that we get is, "can any Fox 7/8" threaded eyelet be used on any Fox shock?". It depends on the shaft and how deep the threads are on the eyelet. A Fox 2.0" shock with a 7/8" shaft has a shorter thread on the shaft and the eyelet is threaded shallower than a 2.5" or larger shock. See the example of the thread length on this shaft photo.

You'll also have to consider the size of the uniball when switching between different 7/8" eyelets.

This eyelet uses a 3/4" uniball. It has a 7/8"-14 thread pitch. It has "deep" threads for any shock LARGER THAN a 2.0". It can be used on a Fox bypass, smoothie, or coil over.