The bag is perfect for the Garmin Zumo 340. Innendrin is an elastic band to store the device wobble-free. There are three external metal eyelets, where you could attach the bag. The strap is in my opinion quite sufficient, because you hold this little pocket anyway rather firmly in the hands than on a shoulder strap.
Who has an odor-sensitive nose, maybe you should nevertheless better buy another product. The bag müffelt quite strong for plastic and must exhale properly. But that is not to be expected for such a low price but different.
