Jessica D Ventura
This mask is designed with a large window that allows full view of the mouth from someone standing in front. It is modified from Montana Mask, so weather strips provide a seal around the face. Air flows through filters installed under the chin, keeping the window from getting fogged up as the wearer speaks.
Complete instructions are available at https://www.instructables.com/id/3D-Printed-Transparent-Face-Mask/