To practice tricks wonderfully, stuck slightly

Super Butterfly trainer. Fits comfortably heavy in the hand and opens and closes smoothly. Unfortunately clamps the buckle to hold it firmly open or closed somewhat, but this is at a training diameter of less concern than it would in a real.
The "blade" know holes so that it can not be sharpened, I find this useful in view of the fact that this type knife is prohibited. The holes give the true optical add something.