Hydroflask Airtag 32/40oz & Thermoflask 24oz Water Bottle Donuts

thingiverse

My daughter lost her cheap water bottle at her elementary school, it usually finds it's way to the lost-and-found in a day or two but this time it seems like it's gone for good since it's been two weeks now. I decided to upgrade her to the ThermoFlask brand bottles since they are cheap at Costco and was actually on sale at $15 for 2 when I went! They even came with silicone boots which our Hydroflasks didn't have. You'll need the boot to use this donut. I decided to make these "donuts" to stick to the base of the bottles to house an Apple AirTag so it would be easier to find her bottle next time. You'll need a circular Airtag holder of some sort, I made the hole for the waterproof holders I already own and use for my surfboard, you can choose other ones. I was initially going to make it so you can just drop an airtag into it, but I think waterproofing would be important for a bottle that needs to be washed often. You simply use 3M doublesided foam tape in the 4 cutouts and stick it to the bottom of the bottle, then cover it with the silicone sleeve. The holes are for weight reduction and water drainage when you wash the bottle. You'll most likely need to remove the donut and apply new tape when you have to change the Airtag battery in a year or two. Decided to make one for my Hydroflask....not that I'm a child that loses bottles...yet. 2022.10.31 - My daughter actually misplaced her bottle a week after I added the airtag donut. So glad I made this! I added a slightly different Hydrofask one as I discovered the multiple 24 holes actually captured a lot more water than single (4) larger holes that drains better. I thinned out the height by 2mm because the bottle has a divot, now MY airtag holder is actually flush once everything is taped down. Lastly I made the tape rectangular pits less deep, I noticed the 3M tape is not as thick as they used to be...probably inflation reasons.