Dual-Layer 5 mm Neoprene Dive Hood, Use with ProEar Mask Dive hood specially designed for use with our ProEar mask line; Constructed with two layers of 2.5mm Neoprene for warmth, durability and comfort; Special stretchable front panels allow for easy adjustment; Smooth skin face and ear seals reduce seepage; Protects your ProEar mask and holds it securely in place.