How long does one can last?

Gel fresheners like this one typically last several weeks depending on cabin size and ventilation. Exact duration varies by vehicle and how much you have the windows cracked or air moving through the cabin.

Do I need anything else to install it?

No. These hang-style fresheners come ready to use—just attach it to your rearview mirror or vent clip and you're done. No fasteners or tools required.

Will this work in a hot car?

Gel formulas are stable in heat, so yes—it'll keep working on hot days. Direct sunlight may accelerate fragrance release, so if you want it to last longer, hang it in a spot that gets partial shade when parked.