[Quantity and Size] The set includes 20 sheets of 3D scanning markers, with each sheet containing 20 markers, totaling 400 markers, with 12mm inner diameter and 19mm outer diameter. [High Performance] These 3D scanning dots have high reflectivity, tear resistant, water proof, sunlight resistant, with high ink absorption and and repeatable adhesion. [Working Principle] Use bright reflective film to adhere a layer of reflective glass microspheres on PET film by aluminum plating, and print hollow circular reflective dots according to specific sizes through screen printing. [User Friendly] Featuring a sticky foil design, these markers are easy to apply and remove, providing accurate data for 3D scanning, reverse engineering, metrology, and inspection applications. [Wide Application] The positioning markers are suitable for 3D scanner in the field of motion information collection, such as 3D motion capturing and gait analysis. The markers reflect the light emitted by the equipment (usually infrared), which is then received by the data equipment for processing, enabling precise data acquisition. Colour:As Shown Material:Plastic Package Contents: 400 x 3D Tracking Dots Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.