Worked very well
My 2 cats had a flea problem so I treated them & the home with Frontline. One cat for some reason still had fleas after a month so did spot-on again but they were still there 2 weeks later. They cause alergy symptoms for her so she's quite uncomfortable. I ordered this flea collar & within 2 days I saw only tiny fleas on her & 2 days later there are no visible fleas & no scratching. I'm so relieved.