Hollis M4 Frameless Low Volume Scuba Diving MaskThe Hollis M4 Frameless Low Volume Scuba Diving Mask features a frameless silicone skirt and a low profile design that fits a wide range of faces while delivering superior peripheral and vertical vision. The low volume silhouette reduces internal air space for easier equalization and a closer, more natural mask feel during dives. The single lens configuration and silicone construction offer durable performance for regular scuba and diving use, with a