Today's watch is a novelty children's watch, but a surprisingly high-tech one.
This watch is a novelty watch from the Nintendo Pokémon line of merchandise. The watch is a standard LCD module with 4 digits and time, date, and seconds displays, but there is an additional button which when pressed makes the noise of the Pokemon Marill. The face of the watch has a Marill design, with the LCD display in its belly. The strap is moulded plastic with the shapes of other water class Pokemon such as Psyduck, Blastoise, and Squirtle.
The unusual feature of the watch is due to the slot on the right side of the watch. With the watch, there are a set of hexagonal 'keys' with a pattern on one side. When this is inserted into the watch, you hear the sound of one of the Pokemon shown on the key. As this is the water Pokémon watch, the sound is of the water Pokémon on the key, and for the keys I have (numbers 2, 3, and 5), I get the sounds of Squirtle, Blastoise, and Tentacool. I've made a YouTube video of the watch working with the different sounds (link).
The watches were released in 2000 as a promotion with Burger King. From the keys, it seems that there were 6 different watches, and at least 5 (I'd guess 6) keys. This should mean 36 different Pokémon sounds from the keys and another 6 from the watches.
The instructions are in 3 languages - English, Spanish (or Portuguese), and German, suggesting this is a European release. These don't tell much about the maker, but it shows the watch runs on 2x AG13 batteries.