1. One-way valve that allows water to drain from the mask

2. Bending of light as it passes through the mask lens

3. Technique to adjust pressure in the mask and ears

4. Metal ring on the mask used for attaching accessories

5. Clarity and range of view underwater

6. Mask with two separate lenses for better depth perception

6. Fellow diver who ensures safety underwater

7. Alternative material to silicone for mask skirts

8. Flexible part of the mask that creates a watertight seal with the face

9. Material used in diving masks for its durability and flexibility

10. Adjustable band that secures the mask on the diver's head

11. Technique used to remove water from the mask while diving

12. Underwater flashlight used for better visibility

13. Type of diving suit that keeps the diver dry

14. Substance or coating that prevents the mask lens from fogging

15. Opening in the mask that allows exhaled air to escape

16. Process of applying a solution to the mask to prevent fogging