There’s no magnet to keep it open, it just sits there but you can invert the cover a bit to make it lay more flat when open. I usually wear it a little lower than chest height and it doesn’t interfere with my draw at all with my bow. Noise wise it’s quiet enough unless you let the magnets close without controlling it.
The main reason I like it is the ability to add pouches and scale it with stuff that I already have like danglers and mag pouches etc for whatever I’m doing. If i just want binos only, then I’m usually using my Rick young bungee harness.
That thing is awesome as well, and is actually my preferred “harness” if you call it that when I don’t need the extra real estate. It sucks the binos right up against you, and allows you to one hand pull them up and use them (while also stabilizing them a bit with the bungee tension) which is really handy while holding a bow.
I can take some measurements later if you want. Feel free to pm me too if you need any other pics or anything.