This is an adaptor to use a bag to inflate a Klymit flat valve inflatable mattress or pillow to prevent humidity from one's breath from building up inside said inflatable.

There are two parts: the actual piece and a test part. The test part is just the upper half that actually connects to the flat valve. I suggest you print this first to see how well it fits, then see if it needs to be scaled up or down a percent or two. If it is marginally loose, maybe use a couple wraps of teflon tape to also protect the valve seal from abrasion from the rough part.

I found that the deflator valve was a slightly different size than the inflator valve. I don't know whether that was intentional, or just a tolerance issue, but the part can be scaled as much as you want. But remember to test on the actual valve you intend to use. Do not assume the other is the same. Also remember to close the deflate valve when attempting to inflate the mattress :)

I just pushed the part through a hole poked into the corner of a plastic produce bag and used a rubber band to hold it in place. I'm sure the part can also be redesigned to work with commercially available pump sacks, but I have none to model from. I did not make any effort to work with electrical pumps/inflators since this is designed for relatively lightweight camping.

Feel free to modify the part as you see fit, it is made using Fusion 360: https://a360.co/2IXkxV5 and I just uploaded the model to the downloads section July 2023.

DIY

Doesn't Matter

No

0.2mm

40%

There are internal slopes just to make the part lighter and use less material. Hopefully the slope on the overhangs don't cause problems, otherwise consider adding supports.