IST Hunter Twin Lens Mask- Low Volume Design & special non-polish finished diving snorkel maskLow volume design: The mask is designed with a low internal volume, reducing the amount of air required for equalization and providing improved buoyancy control. Twin lens design: The mask features two lenses that offer a wide field of vision and enhanced depth perception underwater. Special non polish finished construction: The mask is constructed with a special non polish finished surface, reducing glare and reflections underwater for improved