One factor that makes our folding knives superior to many other known brands is the ceramic ball-bearing pivot mechanism.  It is common for flip-assisted folders to have simply a Teflon or phosphor bronze washer on each side of the blade to act as a bearing.  These will wear out, and don't give the knife the glass-smooth opening action that ball bearings do.  Note the picture at the right, showing a sealed bearing race on each side of the blade, containing ceramic ball bearings.  There is also no spring needed to force the blade open, because the bearings allow for smooth and snappy opening with just a flick.