Depends on what type sharp. On a production folder, I' d say it' s my now discontinued Beretta (Seki made) Electra wharncliffe liner lock with genuine G-10 computer circuit board inlaid panels. This one is RAZOR sharp. It sails thru paper, string, tape, foam, light plastic sheeting with seemingly no effort! As for custom/ handmades- it' s my Dozier made strait knives. I use most of them. And put them to an Extra Fine grade diamond dust covered bench stone when required. These are TOOTHY sharp. Almost akin to microscopic serrated edges. They will rip thru fibrous materials with ease. And surprisingly requires much less time to maintain a real workig edge than polished ones. At least for what I use my knives for. But YMMV.
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