"This product is made for the alpha slate vent as they both have an oval male/ female connecting fitting. Still great value for money. Maybe they should be sold together as a package to stop any complaints. Combined they were still cheaper than other products on the market."
"This does the job and you have no choice if you've bought the slate vent. Does seem a bit fussy though, bizarre shape and could be easier to fit too. Seems as though they just want to make sure you have to use their product!"