The large is the biggest size available for the Imak Arthritis Sleeve, however, below is a link to our CareGiver Product site where we carry the Posey Arm Skinsleeve (Product #:CPO600 ) which comes in XL. Hope this helps and is along the lines of what you are looking for.
https://www.caregiverproducts.com/posey-arm-skinsleeves.html