The great convenience with these knobs is that they instantly convert any standard 1/4" hex-head nut or bolt you supply into a clamp knob. They are particularly handy when you need a knob with a specific stud length to suit an application.
Polypropylene with a textured surface for sure grip, the knobs have a hex-shaped recess with grooved walls to hold a nut or bolt head snugly.
Available in three styles. Nuts and bolts not included. Sizes given are diameter by height.