. The card contains UVB color test strips, which can detect the UVB strength of environmental conditions. Small size and easy to store. Suitable for people with reptiles. Reusable, suitable for detecting outdoor UVB content or UVB testing on card only. Type: UVB test card Size: 8.4 x 5.3 cm Material: PVC Package Contents: 10 x UV Test Card 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 to differ slightly from the actual product. Measurement may vary by +/- 1-3 cm. Instructions for use: Weak and weaker ultraviolet rays will not harm the human body and require no protection. Ultraviolet rays above medium levels can damage skin and eyes and must be protected against. This card is made of ultraviolet color-changing material, which is only sensitive to ultraviolet rays; visible light has no effect. Place the UV-sensitive area of the card in direct sunlight—the stronger the UV in the sunlight, the darker the color change. This card is used to test the intensity of ultraviolet rays in sunlight and can also be used to test the protective effect of anti-ultraviolet products. This card can be used repeatedly and is a helpful tool for outdoor activities, travel, and sun protection.