It is also the basis of the British BESA. Unlike the BREN which was modified to use the British rimmed .303 cartridge, the BESA retained it’s 7.92×57mm Mauser chambering which wasn’t a problem as the Royal Armoured Corps had a separate supply chain to the rest of the British Army and as a bonus could use captured German ammunition. As it was, conversion to .303 was relatively painless compared to creating the BREN but by the time it had reached the prototype stage the go-ahead had been given to BSA to tool up for the Mauser chambering. The 15mm BESA was actually a completely different beast based on the ZB60 m.g. utilising a Skoda-designed 15×104 mm Brno cartridge, basically the same gun as employed by the Germans as the 15 mm FlaMG 39 (t)…
Cheers,
M