well, at first i tried making these and used Diffuser Base, it didnt work well at all...now we sell alot of them using AAA's Room freshener base and it works great ! i sell so many now its hard to keep up even as simple as they are to make ! All my FO's work great with this item, cant complain on any of them, now you will see that the ones that are "light" or "soft" scents wont work as well as others such as your bakery ones or colognes and such, but you know if your customers want a fresh soft scent in a reed air freshener, then they pretty much understand what they are getting. Our measurements are right at 75% base and 25% FO, this seems to be where we stay at with all our scents and it works great, all our customers keep coming back for more ..Hope this helps ! goodluck