Hot eye mask to relieve eye strain and improve sleep quality. - Type: Hot eye mask - Package contents: 2 sets of 10 masks each - Effect: Relieves eye strain - Usage time: Approximately 30 minutes of heat effect Thank you for viewing. I purchased a set on SHEIN, but I have too many, so I am selling them. Brand new, unopened. The duration is long, and the temperature is just right, so it's useful in winter. Good for travel and eye strain! Bulk purchases are also available! If you have any questions, please feel free to comment.