Feature: 1. Before use, rinse with clean water and wipe dry. 2. Loosen the headband and place the mask at the bottom of the face. 3. Put the headband firmly on your head and make sure you put on the mask. 4. By adjusting and ensuring that the mask is comfortable and tight. 5. Check that there is no gap between your face and mask. 6. Children under 12 must be worn by adults. Specification: Material: ABS + PC + silica gel Lens material: antifogging lens Frame material: Platinum vulcanized silica gel Equipment combination: plug in breathing tube Waterproof performance: track buoyancy ball Color: Dark Blue Specification: S/M, L/XL Weight: about 570g Size: S/M: Inner diameter 17x13cm/6.69x5.12in, outer diameter 23x19cm/9.06x7.48in L/XL: Inner diameter 19x13cm/7.48x5.12in, outer diameter 23x19cm/9.06x7.48in How to use and remove the mask: Put on the snorkeling mask and put your head in the water to make sure that no water enters the mask. Breathe naturally when the dry top is on the water. Put your fingers on the mask and your chin, then push the mask up over your face. Maintenance: Place in a dry place. Do not expose to sunlight when not in use. Clean and dry the mask surface with lint-free/scratch-free glasses cloth. After use, rinse with water and air dry. After being used in seawater, salt is removed by soaking the product. Put in warm water for a few minutes and air dry. Warnings and guidelines: If damaged, do not use a mask. Before use, please check for cracks and tears. Use only in water. Diving into the water with a mask is not appropriate. How to choose a size? First, measure the length from the eyes to the chin. If the length is less than 13.5cm, please select S/M (suitable for teenagers and adult women) If the length is equal to or more than 13.5cm, please choose L/XL (suitable for adult male) Tip: This product does not include camera Note: 1. Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you 2. Please allow 1-3cm measuring deviation due to manual measurement.