Relum Jelly LP 25 (or Telly with a German T on the disk that is/was on the stock).
One of a number of break barrels that were made for Relum by the Hungarian FEG armaments factory.
They also made a a smaller break barrel, the 822 LP23 0.22” and 877 LP22 .0.177”.
In the 70s these models were dropped for a new range of guns, the 422 (Taurus), 522 (Rapide) and 527 (Zephyr), the last of which is still in production.
Relum (Muller) also imported guns form other E European countries and relabeled them.