Use an empty paper towel roll. You can use it plain, paint it, or decorate it. It is a great craft projects for the kids. Stuff it full (will hold about 5) with plastic bags. It will fit inside console or pocket on you vehicle. Great for putting trash in, especially when you have children.
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Hate all those plastic grocery bags laying around? I stuff mine into paper towel tubes and store them in the vehicles for emergency spills or garbage bags.
Use a carabiner to attach the bag to your car seat. That way you can have your stuff organized. You can use a shower hook as well.
