Thank you very much for your interest in Cobra products! You mentioned the Cobra Beach Tennis System and being able to use it for Badminton? Yes, you can purchase a Badminton kit for the Cobra for $98.00 and it includes a high quality badminton net and boundary line adjustable to singles and doubles play on sand or grass. As you know you do not need "sand kits" for the Cobra system on the beach.  Click here for link to website