Thumb Stud/Disc - Opening Systems
Thumb Stud/Disc Info
A thumb stud or thumb disc is basically a protrusion from the side of the blade that allows you to use your thumb to open the blade of a folding knife with one hand easily. You simply place your thumb on the device, and push against the blade and move your thumb in a semi-circle, opening the knife.
Some knives used thumb discs, some use thumbstuds or some other sort of protrusion from the blade. All are designed to do the same thing: Add something to the knife to make it easier to open it with your thumb.
Some thumb studs are dual purpose. Not only do they serve to open the knife, but they can double as a stop pin. Additionally, some thumb studs are not actually thumb studs and only look like thumb studs, such as in the case of the Strider SnG. The SnG actually uses a thumb hole, but has studs that serve as stop pins next to the thumb holes.