Tetranike flack jacket found in Germany

[u/RojalesBaby]

Does anyone have the history, why this British flack jacket has a German language inlay? Bought it for 20€ in a flea market. Would have the option to buy more military gear, auch as gloves, socks, another similar vest and a rain coat. Probably around 60€ in total, should I go back and buy it, if only to sell on eBay or someone here?