How long does one can last?

Gel fresheners work slower than liquids, so you'll get several weeks of scent from the 90-gram can. Duration depends on temperature, ventilation, and how strong you like the smell in your cabin.

Can I hang this from my rearview mirror or does it need to sit flat?

The rabbit ear design is flexible — set it on your dashboard, place it in a cupholder, or hang it from your mirror. Test the weight first if you're clipping to a vent to make sure it stays secure.

Will this stain or damage my dashboard if it leaks?

Gel formulas are less prone to spilling than liquids, but gel can still transfer color or residue if it makes direct contact with lighter surfaces over time. Keep it on a surface you're comfortable with, and wipe any contact spots occasionally.