I purchased these refills at the same time that I purchased the flea trap. There are no fleas in this area who are willing to step on these sticky discs. As a result, the flea trap is of no use to me. These refills are of no use to me as well  and that is why I can give only one star. They cost only $5.76 which is too small an amount to consider returning this item. I plan to offer the flea trap and the refills on the local freecycle website in case there is someone who has a flea problem and wants to try this option.