Optical sound for 9.5 mm, introduced by Pathé in 1937, was used only for reduction prints from commercial films (Gourdet-Marès 2024). Pathé reduced the width of the image from 8.2 mm to 7.3 mm to make room for the soundtrack. Magnetic sound on 9.5 mm, which allowed amateurs to produce home movies with sound, didn't become available until 1951 (Gourdet-Marès 2024b);

Sea Kings was a short subject included in a 1940 Pathé Pictorial. Pathé Pictorials were film "magazines" containing a selection of light segments (Newnham 2019).