Wonderful fun! Cheaply made

We were warned not to put rats in a rat ball because it could hurt their spine after research we found that this is only a problem if the ball is not large enough.Our sweet rat "Princess" is full of energy and likes to run and we feared losing her. She comes when called however if she climbs up inside the couch we cannot reach her and she will gorge herself on the crumbs that the vacuum cannot reach. She will not come while eating the crumbs and we feared eating this junk food would make her sick or worse.
We got a large rat ball (size "Giant" about 11 inches in diameter). Princess is full grown but on the small side and this ball almost seemed too large for her but turns out to be the perfect size.
Princess LOVES her rat ball; she will beg to go into it! We keep it next to her cage and when we pick her up she tries to wiggle toward her ball. She is a smart rat and she has learned her way around our house. She rarely crashes but she will slowly bump into things that she is trying to get a closer look at.
She has routines that she likes to follow first she goes around the whole house several time checking her boundaries. We bunch a couple of rugs up to prevent her from going into the bedrooms--and if we forget to put those out she will beeline to the new space since she loves exploring.
If we slip a thin piece of ham or cheese or apple through the ball air slits no matter where she is in the house she will carry the treat to the kitchen and go under the dinner table where she sits to eat. When she is done eating she goes back to her rounds.
One of the amazing things she does is whenever she has to go potty she will actually go down the hall into our guest bathroom (which has no windows and is dark) where she will go number one and number two. Obviously if she starts to roll she will get dirty but she DOES NOT ROLL! She stays in that bathroom in a dark corner; until we notice. Then we take her out wash the ball and put her back in. Then she continues on her happy way.
One big warning is that even though the slits in the ball are really narrow she can use her fingers to pull inside any soft material she finds she has pulled inside a plastic bag (yikes!) rug fringe and even the thick curtain (in which she gnawed a hole!). Now we keep everything off the floor and we've blocked all the curtains from her.
Princess likes to follow the dog around the house. He is a large calm dog but he doesn't care for this attention. Princess will follow him and if he lies down she will bump against him. He basically ignores her but occasionally he will walk away and cross the bunched carpet to lie down where she can't get to him.
The biggest problem with these rat balls is that they are sooo cheaply made! The thin plastic door holders snap off. Cracks form around the doors and grow. We have Gorilla glued this ball several times just from gentle use (it has never been dropped).
The last two times Princess was in her ball the cracked door popped open. So we have not put her in it in a week and she has been mad! We can tell she wants to go in but doesn't understand why she can't.
We need to buy a new one soon. PetSmart has this size ball in Clear for $24.99. Pet Club has the same ball but in yellow for $19.99 but we really wanted it in Clear. I can't find the 11 inch ball on Amazon.
TIP: To help your rat have a positive experience in the ball use food. Every single time you put your rat in the ball give her a special treat like a slice of cheese. Soon your rat will have no fear of the ball and will see the fun of it. (of course the rat should NEVER be pushed or spun or kicked while in the ball otherwise she will hate it.) We reward the same way after holding her. Every single time we put her back into her cage we give her a special treat so she looks forward to going back in.
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