As much as I like how they look, I generally tend to avoid LARGE slip joint knives as "users" (due to the fact that the blades typically don't "lock"). However, there are a few manufacturers that make large slip joint knives where the back-springs are strong enough that I generally feel "OK" about using them. Great Eastern Cutlery is one such manufacturer. The knife shown here, in Frontier Bone, is one good example. There are no locking mechanism on the knife (lockback or liner lock). Instead, the back-spring is just good enough to make this viable for general EDC use. I wouldn't tackle "hard use" tasks with it, of course...but is a good tool for general chores.