Among the hardest to find of the standardized Japanese grenades, for a couple of obvious reasons.
On the left is the Frangible Glass Smoke Grenade. All of the US references list it as Type unknown, I am sure that there is a Japanese designation but I have never been able to confirm it with actual documentation. References identify it as being filled with a mixture of titanium tetrachloride and silicon tetrachloride. On the right is the grenade identified in US manuals as the 172 B-K Gas Grenade. Filled with Hydrogen Cyanide (HCN) it was a bona-fide chemical weapon, though of limited effectiveness. I've had the smoke grenade for some time, but got a tip last weekend and just received the HCN grenade today. I've only seen one other.

On the left is the Frangible Glass Smoke Grenade. All of the US references list it as Type unknown, I am sure that there is a Japanese designation but I have never been able to confirm it with actual documentation. References identify it as being filled with a mixture of titanium tetrachloride and silicon tetrachloride. On the right is the grenade identified in US manuals as the 172 B-K Gas Grenade. Filled with Hydrogen Cyanide (HCN) it was a bona-fide chemical weapon, though of limited effectiveness. I've had the smoke grenade for some time, but got a tip last weekend and just received the HCN grenade today. I've only seen one other.
