This is a remix of the Inflatable SUP/Kayak Halkey-Roberts Valve inflation adapter posted by lieutenantglorp here: https://www.thingiverse.com/thing:2354966 . It was too small for my hose which is why I remixed it. It should fit most inflatables, but your pump hose outer diameter may vary. I use it for my inflatable Hobie, so I know it works with that brand. Due to varying hose sizes, I have attached the file I modified in Fusion 360. My pump hose was 25.95 mm. My guess is that it was supposed to be a 1 inch hose. Anyways, to easily adjust it to the size you need, use the "modify" tab, then select "press/pull", then click on the inside tube wall and make it larger or smaller. I did not find it necessary to add a gasket.
I believe I used supports, but it was a while ago and I can not remember for sure.