DtM-v3 Remix with strap buckles

cults3d

This is a remix of Timothy Prestero's NIH compliant face shield, from https://3dprint.nih.gov/discover/3dpx-013359 I added another fastener to the back of the shield frame to accommodate a strap that doesn't have the buttonholes. This works well with the 3/4" (19 mm) wide elastic strap I could find locally and fits securely. 5/15/2020 I updated the .stl file to now include small chamfers on the bottom edges that touch the forehead as well as the shield. This reduces/eliminates the sharp edge where the print adheres to the print bed, which could cause a mark or cut on the wearer's forehead, as well as making a more flush fit for the shield.