With the Jackson Galaxy Space Station, you're able to watch as your cats hunt for the rolling ball through multiple openings, both inside or outside the 'bridge' of the space station. Not only can YOUR kitties hunt and stalk to the rolling ball around, they can also lounge inside the giant elevated bowl and scratch at the corrugated cardboard floor at the station's center.
If you wanted replacement balls for the Space Station, you can use the LED balls that come with the Galaxy Spiral, from the same Jackson Galaxy line. Or if you're a frugal feline family, like mine, we used golf balls and other cat puffs we had floating around the apartment. As of this review, there were no replacement cardboard refills available. But if you are into DIY, it wouldn't take much effort to cut your own, to get the most bang for your buck with this large toy.
I would suggest supervising your fur-babies when they start to play in a galaxy far, far away because some of the holes on the elevated bridge station could be large enough for their curious heads to get stuck in the opening. Give them time to get used to it and you can bet this will be a winner in multi-cat homes.
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