This is a 33.5mm. circa 1990’s Baume And Mercier Moon Phase Chronograph Complication having a (just cleaned) LEMANIA manual winding movement that is visible from the sapphire case back. Notice the Guilloche dial with mother-of-pearl chronograph registers, spade hands, moon phase, date and chronograph complication. The cabochon-tipped winding crown adds further appeal to this classic watch. This is a bargain at this price!