From the late 1930s until at least the early 1950s there was a rival daylight-developing tank system to Agfa’s Rondinax.

This is shown on the superb Photographic Memorabilia website:

The links from there are well worth following since they show how these tanks operated as well as photographs. They were made by by Friedrich Fischer of Austria. This company must have had a hard time working round the Rondinax patents and the products, especially for roll film, appear to be complicated. Essentially, the reels are vertical, as in a conventonal darkroom-loading tank, and the films are fed in from a slit in the side; the slit is then closed by a leak-proof door after loading. One of the roll film tanks appears to be complicated to operate, with the film being fed from the outside into the reel (as in loading a conventional tank) as the backing puper was pulled. There was one advantage: within the range was one for 127 film and another, a universal, for 127, 120/620 and 116/616 film sizes.

The Photographic Memorabilia website gives the slightly misleading impression that the Essex continued the principle of loading 35 mm film into the spiral and then cutting the film. The Essex was, of course, derived from the Rondinax 35 which got there before the Austrian designs.

The 1937 advertisements from the British agent name these tanks as the Superkino (35 mm), Simplex (120/620), Super-Junoplex (127). The Superplex or Superflex was advertised in 1952; it was the universal. Photax, the well-known importers and agents of photographic goods, was the British agent in 1952. They were also imported into the USA in 1937 as this link from Flickr, showing the US agents and making a dubious claim, demonstrates:

Simplex and Superkino Daylight Loading Developing Tanks 1937

Judging by the rarity of these tanks on eBay, they were not a popular buy. They can be classified as tanks to collect rather than tanks to still use. I would really like to try using the rollfilm models though to compare them with the Rondinax 60.