One-handed opening is a frequently marketed feature and an occasionally necessary one. If you carry a bag, have a dog on a leash, are frequently gloved, or work in environments where both hands are rarely free simultaneously, deployment mechanism is a real differentiator — not a fidget-toy spec.
We filtered the CarryIndex database for every folder under $150 with a confirmed one-hand deployment mechanism: flipper tabs, SpeedSafe assisted opening, Spyderco thumb holes, thumb studs with wave features, and OTF automatics where legal. Then we ranked by price, because under $150 the value distribution is wide enough to matter.
Legal note: Assisted opening knives (SpeedSafe) are legal in most US jurisdictions but check your local laws. OTF automatics have more restrictions. Thumb holes and flipper tabs are legal virtually everywhere.