This product is made of high quality 3mm thickness neoprene rubber. Wearable head circumference from 55cm to 62cm.
 
Please note: If this mask needs to be connected to a breathing bag, the mask needs to be modified, and the modified mask will not be able to use the breathing bottle
 
      If you have any questions about the product, please leave me a message because of the time difference. I may not be able to reply to you immediately. I will reply to you as soon as I go online