?Size?The diameter of the patch is 3.03 Inch. ?FDA registered material? The material of Kovoq sensor cover is FDA registered and CE certificated. Every patch is made from medical grade adhesive that is latex-free, and hypoallergenic, which makes it suitable for all skin types. ?Waterproof & Swearproof? The Kovoq CGM patches are made with latex-free breathable cotton fabric and strong wave-patterned adhesive. They are also waterproof and sweatproof, holding the sensor firmly to your skin for 7 to 14 days. It works well while showering, sweaty exercising, swimming. Wear it and forget about it. ?Size?The diameter of the patch is 3.03 Inch. ?Reusable Hard-shell Covers Included for Stronger Protection Than Adhesive Patches Only? Adhesive patches for Libre Sensor come with reusable hard-shell covers, give you strong anti-shock, anti-knock and dirtproof protection rather than traditional adhesive patches which just provide you slight protection and some fixation. The hard-shell covers are specifically designed for FreeStyle Libre 1/2 without blocking the airflow nor affecting the data reading. ?One Hand Operation, Easy Patch? The three-part release liner and the grip-design of Libre sensor covers make it extremely easy to stick the patches by one hand operation. Compatible with: Abbott Freestyle Libre, Libre 2, Libre 14-day, Libre Pro.