This item is for sale on GunBroker at https://www.gunbroker.com/item/887400010
Made by Medef Defense Limited, Cyprus & Ankara, Turkey and headstamped for GROM (Wytwórnia Amunicji Grom) a company in Poland. The brass plated steel case is not common. Details on GROM at https://forum.cartridgecollectors.org/t/pl-wytwornia-amunicji-grom-poland/26797/5 . It is not clear why these would show-up in Venom boxes. No previous GROM marked cartridges have shown up in the US as far as I know!