There are many useful health wearables on the market, but you only have so many wrists. This allows you to fit an Aktiia G1/ Hilo blood pressure monitor on the wrist strap of a Google FitBit Air so you can use both without your wrists looking ridiculous.

This has only been tested with the band included with the Google FitBit Air.

Instructions

There are two models, one with a ~2mm depth for the band, another with a ~3.5mm depth. I have found that the 2mm depth provides the perfect friction for the band. You may need the 3.5mm depth variant if you have narrow wrists and need to pass the excess band back through the adaptor so that it doesn't get in the way of the Aktiia/ Hilo sensor or need to be rolled/ folded uncomfortably.

Slide the adaptors onto the band as demonstrated in the photo, then clip the Aktiia/ Hilo into place. Place the strap on your arm and then adjust the positioning as required.

Warning: The model is about as small as it can be before becoming structurally useless, this means it won't hold up to a lot of abuse - some sections are only 1 wall thick, but these should not be taking any strain frequently as they're on the outside of the strap. Print with a tough, non-brittle material.

Print settings

Tested with the following print settings

Nozzle: 0.4mm
Layer height: 0.1mm
Material: Prusament PCCF