Note: Please allow 1?2cm error due to manual measurement. Thanks for your understanding. specification: Item Type: Sensor Covers_x000D_Size: Approx. 10 x 8.5cm/3.94 x 3.35in_x000D_Material: TPU Features: 1Easy To Clean: Easy to remove and easy to tear off the backing sticker makes sticking a breeze. 2Waterproof Design: This sensor patch is waterproof and breathable, it allows your skin freely breath while protects. 3Easy To Use: Sensor patches can be used for running, walking, swimming, bathing, and doing your daily activities. 4Comfortable, Thin And Flexible: Sensor patches can support the body's natural range of motion, these patches are hypoallergenic and latex free, safe and non irritating. 5Patch Has No Holes And Glue: Middle is designed with a pre cut to keep the sensor and make the patch more secure. PackageList: 10 x Sensor Covers