Would CCW for handgun also cover a knife?
BTW - What is a gravity knife?
A gravity knife is similar to a switchblade in that the blade can be opened one-handed with no resistance, then locked into place, but is not spring loaded like a switchblade. A flip of the wrist will do it.
Thumb assists and cutouts in later blade designs have rendered the average larger folding knife similarly amenable to rapid deployment, and without the excess movement.