Strength Shop Double Ply Thor Knee Sleeves Review Leave a reply Strength Shop ‘Thor’ super heavy double ply knee sleeves (price per pair). To get your measurement/size please measure around the middle of the knee when straight. S – 11″ – 13″ M – 13″ – 15″ L – 15″ – 17″ XL – 17″ – 19″ XXL – 19″ – 22″