for black onyx version, couldn't get it on my Gibson All American II which has a fairly wide knurled split post etc. I have yet to be able to mash them on there by just pushing them on and I don't really want to start bashing on the guitar/pot. They look good and would compliment the guitar finish/black.

for black version which has a different recess/mount/hole... I have a Gibson All American II and was able to easily push these on snug, whereas the metallic black version has a completely different recess/mount/hole type and I couldn't push them on at all yet.

Like another reviewer I replaced the hard to see knobs on a Supro Blues King 10. These knobs look great, they fit well, plenty of space, and look like they were made for the amp. Very easy to see where the know is set and match the amp well.

The quality on these is very good. I used them to replace the stock knobs on a new Supro guitar amp. The stock knobs were round skirted and only have a small dot on the skirt so it’s very difficult to see where they are set without craning your neck and getting just the right angle of view. These chicken head knobs suit this application much better and the settings can be seen from any angle.

Product itself is excellent.
Could have done with better description of it on website.
I thought they would fit a standard Fender Stratocaster CTS pot or a Deluxe amp pot- wrong!
Hence I am ordering three more with grub screws - trust they will be of the correct size.
Caveat emptor.

This review is for the "glow in the dark" knobs.
Please be aware that these are black knobs with a tiny glow lines that will only "glow" in the pitch black! They will not be useful in a dark bar or dark club setting as they won't be visible unless it's well lit or completely dark. What's more is that they are still being sold as glow in dark, but are useless in the semi-dark where they are needed.