The bacteria killing formula can last up to 6 months.
Yes, while the recommended application of this product is through the drain tube, depending on the ventilation setup, you may apply this cleaner via the vehicle's interior vents.
Yes, Lubegard's Kool-It Foam Cleaner can be used with any enclosed HVAC system susceptible to mold, mildew, and bacteria. Use proper ventillation when applying the cleaner