You are all so close.
The design came from us, well sorta. It is the the same size and has the same framentation pattern as the old M406(HE)round/cartridge. SOG warriors and Vietnam Vets in general will recognize this round as the round used in the M79, XM148, and later the M203. The Dutch just took the rear portion(actual "grenade") of the M79 round and put a Bouchon (modified) type igniter/detonator on it. Plain and simple. By the way, when the Dutch found out that Mr. Baker (CISO) was purchasing them to be used in The Vietnam unplesantness they stopped shipping them to him. Seems they had always been against our involvement in what they coined as a "Vietnamese Conflict between the Vietnamese people only". Sounds familiar doesn't it. Just FYI
