Why were Gravity Knives ILLEGAL in the first place?

Unique & Innovative OTF GRAVITY Knife | Remette RT Swordfish

This new EDC Utility Knife does something I've never seen before! (Pichi Design G9)

3D-Printed Utility Knife Assembly #thingiverse #3dprinting #knife #utilityknife #gravityknife

Paragon Warlock : Gravity Knife Review

WWII Gravity knife

Reate EXO-M Review - One of (if not the) Best Gravity Knives on the Market

Mini Gravity Knife! Illegal to carry legal to own

Aga Campolin Dragonfly Gravity Knife - Overview and Review

Reate Exo Gravity Knife: The Most Illegal Folding Knife in the World.