I discovered a long time ago that the chemical used to keep the ants away is not important. If you will notice how this little contraption is made, there is no way ants can get to your feeder from the bottom hook. They would have to crawl down and up into the guard, then down and over the bottom piece to the top of your feeder. I have used the same guards over and over for years and I have never seen an ant to that.
I take my feeders down after a week goes by without any Hummers in our yard. I wash all the feeders with dish soap, including the guards. I store them in a cabinet in our studio until April the following year when Hummers usually return to Middle Tennessee.
I save a bunch of money by reusing the ant guards and have the added bonus of no harmful chemicals around the birds too.
For more about Hummingbirds see: