The Sy-Klone is Absolute brilliant and the best intake for any snorkel system on the market.
Unfortunately measuring things for the old historic measurement system is inaccurate and I had to find out later online the more precise metric system a discovered that snorkel head is actually slightly bigger than 4 inches which meant it was too big to fit easily on my snorkel.
I then tried fitting a reducer adapter But also this measurement is not very accurate and was too small to fit my snorkel yet they head was too loose on the Snorkel even for tape to take up the space.
The adapt is also very short and a bit of a band-Aid compared to the awesome design.
The needs to be a number of better designed and made adapters which are also much taller to fill in the space which is approximately 55 mm high/long.
I had to go and get local shop to fit the supplied reducer adapter into a lathe and then send down to make it fit.
My long-term plan is to go and get some aluminium tubing and get a machine to size and then slit and glued onto my Snorkel to make everything fit for more professionally.