TAC-FORCE TF-912GN SPRING ASSISTED KNIFE. 4 3MM THICK BLADE, STAINLESS STEEL. Check Out this Spring Assist Tactical Folding Knife Product Video. An assisted-opening knife is a type of folding knife which uses an internal mechanism to finish the opening of the blade once the user has partially opened it using a flipper or thumbstud attached to the blade.The item "Tac-Force Black Plain Blade Green Tactical SPRING-ASSIST FOLDING POCKET KNIFE" is in sale since Wednesday, April 1, 2020. This item is in the category "Sporting Goods\Hunting\Knives & Tools\Folding Blade". The seller is "my_beyondstore" and is located in Covina, California. This item can be shipped to United States, Canada, United Kingdom, Mexico, Germany, Japan, Australia.