Yes, these go off on impact.
These do have a pull pin that prevent them from going off, its the green line line you see on the top of each grenade. That is the "Safer Pull Pin". Its used as an alternative to a cotter pin and key ring which is quite sharp and can puncture things. This style has no sharp points.
They will not go off accidentally. I have had 2 out of almost 400 made break from the stress put on the latex tubing, but that can happen with any grenade out there, even the "Big Boy" grenades. But mostly they won't go off until you pull the pin and throw.
Let me know how many and what color. I can get you a quote and a time by which I can have them shipped to you.
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