I have something called a Batzibelt for Kona. It is a ring (sort of) that goes on the seatbelt - the seatbelt is buckled like someone is sitting in it. Then it has a strap that attaches to the ring and her harness. It is adjustable longer or shorter. Kona is able to still see out the window and wander a little bit on the back seat if she wants to, but I have the peace of mind knowing that if I have to hit the brakes suddenly she won't go flying and if something were to happen she could not go running off on her own scared. I liked it so much I bought 2 more for our other cars. The ring can come off so I can put her in the front seat if I want to. The ring also stays on and won't interfere with a human passanger if I need to take people.
Here is a link - I hope it works!
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