See link in Acknowledgement for instructions. I am not liable for how you use this mask, or what your expectations of it are. The modifications to this mask: * Thinned interior of mask by 0.50mm for increased flexibility * Raised nose bridge * Pulled tip of nose bridge in toward face * Added sealing flange for the insert to seat against * Added features to decrease empty space between insert and mask housing inlet You should augment the instructions from the link above, with the following suppression: * Place Filter media over insert, and press into mask housing inlet from the FRONT of the mask. to ensure proper fit, press front of mask down on something flat. This ensures insert will seat well against the new sealing flange I've added. ------------------------ The 3D printed mask information presented here is intended to assist the general public during the current a global pandemic related to COVID-19 and the related nationwide shortage of personal protective equipment. Please be aware that this mask design is not intended to replace standard protective equipment such as N-95 masks or surgical masks when that equipment is available. The use of these 3D printed masks has not been fully tested and has not been approved by federal or state authorities.