Does any one have any recommendations for car hammocks. I'm looking for something to keep the pups (mostly Sawyer) from falling off the seat in the back if I need to stop quick so they don't hurt themselves. It needs to be able to fit in a small car (and if possible also be able to fit in a larger car but not a requirement), have enough room for 2 dogs, have the ability to use a doggy seat belt, have good traction for their paws (Sawyer isn't a fan of car rides so he frequently moves around and stands up if I slow down or stop), and I'm looking for something in the $0 to $60 range.