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I know it's not a dog toy technically, but my guys chase after these and would destroy the fox den, given half a chance.
These products take 3 AA Batteries not 3 AAA as I said in the video.
FroliCat Laser Cat Toy and Fox Den
From the manufacturer:
FroliCat® MULTI LASER
The FroliCat® MULTI LASER is an enticing, automatic toy featuring two Lasers for cats to chase. It’s great for one cat or a few, and the easy on/off feature and automatic shut off make it the perfect toy for pet parents who are on the go!
FroliCat® FOX DEN
Let your cat have some fun and give it the FroliCat® Fox Den Automatic Cat Toy. With easy on/off features and automatic shut off, your cat will be playing with this all day.