Unknown (but surely French) propeller in one of the Polish Potez XV. Produced approximately around 1923-1924. Attached to the engine Lorraine Dietrich 12DB (400HP). Despite relatively good quality it is hard to say what was the producer. It looks like Merville is one of the posiible option. Picture received from Robert Gretzyngier. Many Thanks!
Period Advert. Ratier 1924.