Thanks for the likes, Angelo, jale, JMBL and Luis. And for the posts, Pete, dmaziuk, Iowwall and Luis.
Now for the Nemrod PS/2045 snorkel. Here it is in 1955:
Spanish: "
PS 2045. Respirador plástico infantil para niños de 4 a 9 años".
Rough translation: "
PS 2045. Child's plastic snorkel for children from 4 to 9 years old".
So a snorkel with head bracket and band, drain valve at the bottom and cap valve at the top, all designed for young people in their first decade of life. I am presuming that the cap valve operates in the same way as the following Typhoon breathing tube made in England:
The "splash cap" is a "wave deflector" in modern parlance and is the key component of a "semi-dry snorkel" that keeps water from entering while the swimmer is at the surface in choppy seas. It works by have air inlets inside a rubber housing fixed to the top of the barrel and fitting loosely at the bottom to admit air from outside. Water will enter when the swimmer's snorkel is completely submerged.
Here is the Nemrod model in
1962:
Spanish: "
PS/2045. - PLÁSTICO INFANTIL CON BOYA. - Especial para niños de 4 a 9 años. Con turbante-brida y boya especial".
Rough translation: "
PS/2045. - CHILD'S PLASTIC WITH VALVE. - Special for children from 4 to 9 years of age. With head bracket/band and special valve".