Bests & Worsts Reviews from Amazon

Killed all my cats fleas and my older cat had NO adverse reactions to the collar BUT There is a serious design flaw in the collar. You must be absolutely certain before placing the collar on you pet, you have removed all cut "nibs" from collar or you may experience sad and expensive consequences. When you open the package for the collar, you will discover it is in spiral with "nibs" leftover from the manufacturing process. These "nibs" holds the collar in its spiral shape. If you merely "cut" these "nibs" once to unroll the collar and then place it on your pet, bad things MAY happen. If only cut "once" you will leave sharp and dangerous "fangs" on the inside of the collar. These "fangs" can cut into your pets skin, delivering its pesticide directly into your animals blood stream. Very, Very Bad. If you take your time and make sure the inside of the collar is smooth by removing these "fangs" with a sharp knife, I believe you will have a much greater chance of a flea free happy pet outcome. I cannot be for certain but I believe many of the negative ratings of the collar are a result of this flaw.