The Hollis M1 Mask is about the pricier side, but its progressive structure and high-quality components make it a worthwhile expenditure for serious divers. Presently once the covid-19 pandemic, there are a few face masks which are made up of the silicone product. This mask has an ergonomic, frameless design https://sovietmm1gasmask38372.bloggosite.com/35024438/the-single-best-strategy-to-use-for-silicone-mask-making-kit