I bought a couple of Renuzit push up air fresheners for my bathroom and when they dried out, I renewed them by pouring some sea salt in the bottoms of the containers and adding several drops of lavender oil onto the sea salt. I gave the containers a slight shake to incorporate and it became an air freshener all over again that lasts for over a week! The scent of these now recycled air fresheners are actually a little more powerful than the original ones I initially bought from the store. I can recycle them every week or so for pennies by just adding a few drops of essential oils. Wow, this is great. Hope this tip proves helpful for you.