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There are many models designed to fit over the tail gate of many common models. Some are smaller and simply create a little extra space with the gate open. Others create an entire room off the back of the vehicle with screened windows and room for the family. This choice is a matter of personal taste, budget, and intent. Another solution, which can compliment a truck tent or be used solo is a product called the "Magna Screen". These allow you to sleep with your windows down and provide a barrier against insects. Basically, a Magna Screen is a screen that fits magnetically over the exterior of your side window. They're inexpensive, durable and solve the problem nicely.