. The card contains UVB color test strips, which can detect the UVB strength of environmental exposure. Small size and easy to store. Suitable for reptile owners. Reusable, suitable for detecting outdoor UVB levels 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 is included; other products are not included. Note: Lighting and different displays may cause the color of the item in the picture to appear slightly different from the actual item. Measurement allowance is +/- 1-3 cm. Instructions for use: Low and very low ultraviolet radiation levels are not harmful to the human body and do not require protection. UV levels above moderate can damage skin and eyes and must be protected against. This card is made of ultraviolet-sensitive color-changing material, which reacts only to ultraviolet light; visible light does not affect it. Place the UV-sensitive area of the card under sunlightthe stronger the UV in the sunlight, the darker the color becomes. This card is designed to test the intensity of ultraviolet rays in sunlight and can also be used to test the effectiveness of UV-protective products. This card can be reused and is a helpful tool for outdoor activities, travel, and sun protection.