George Davenport popularised the effect after the company purchased the rights through Max Holden from an unknown American source in 1930. It was a huge success and has been sold by Davenports ever since. I have a few examples in my collection. The one shown below has the striking red and yellow packaging synonymous with Davenports with a text description of the effect stamped on the box.
The apparatus itself is in remarkable condition with the original packaging on the blades. The trick was improved by Robert Harbin with the addition of the gimmicked spool of thread, removing some of the more complicated handling. He gave these improvements to Davenports and they printed them along with the original instructions. The trick also came with a handy block to make the resetting of the trick straight forward and to avoid tangles.
This example has a few differences, the most obvious being the packaging. This has slightly rarer graphics with the clown face more generally used for jokes and novelties. It also has a wonderful stamped image of the trick, clearly based on the photograph of Gilly above.
These also come with some extra envelopes showing that the blades have been chrome plated by Paisley Cooperative Manufacturing Society Ltd. This was presumably done to make them even more showy under the spotlights and was done after they were purchased. Gilly performed this effect for Movietone News in 1931 and Jasper Maskelyne performed it for Pathé in 1937.
Performed live it is a striking, stage filling trick that personifies the "packs small, plays big" idea. One of the best live performances I've seen was the late Bunny Neill performing this. He produced a string of blades long enough to stretch right across the stage, a brilliant sight.