These are solid milled barrel knobs. Markedly shorter than Tele-style knobs. They are solid milled metal (not a metal sheath with a plastic push-in insert). They are affixed to the shaft with a 2 mm Allen/Hex key/wrench. Be careful if you mount these on split shaft pots as they can squeeze the split-shaft together. As these are shorter, you may need to 'float' them a bit higher on the shaft. Because of that, you'll find it difficult to get them to be perfectly flat as you tighten the set-screw. So, they'll look a little wobbly/off-axis as you turn them. They have a nice drilled index-mark through the Chrome plating to the brass; that helps see where you are. They are solid, heavy, quality pieces. I'd prefer a press-in type unit, but of this quality, to avoid the issues mentioned above.