Used Dog Collars For Sale

Hartz Ultra Guard Flea and Tick Collars for dogs?
Okay so I heard a lot of really bad things about Hartz products and I was wondering if anyone has used these collars or if anyone knows if they are safe for pets? We are going to be walking in a wooded area and I want to make sure my pets are protected and last year my husband picked a few of the collars up at the end of the year when they were on sale but I don’t want to use them if they are going to make my dogs sick. Thanks!
Flea Collars do *NOT* work! And Hartz is a HORRIBLE band! So is Sergeants, Adams, and Bio-Spot.
I would use Frontline Plus, or K-9 Advantix. They might be expensive, but they WORK!
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