This design is optimized for user experience, reduced print speed, reduced material use, strength, and modularity/versatility! It addresses several issues I've identified with the popular "gull wing" style Ear Savers (features list below). I've provided over 1,000 to local hospitals and the community with rave reviews!

For the Ultra Lite model, these are my print quantities and times:
CR-10 - 20 Straps - Speeds: 100% = 4:30, 150% = 3:45
Ender3 - 13 Straps - Speeds: 100% = 2:45, 150% = 2:20

For the Ultra Lite model I'm getting ~632 straps per 1kg spool of PLA+ material.

This design Is optimized for .4mm nozzle and .28mm layer height. The final part is .84mm thick (Ultra Lite Model) or 1.2mm thick (the other models), providing excellent strength and flexibility when printed with standard materials like PLA! See the Print Settings section below for slicer settings/tips.

Print Settings:

I use Cura but many of the settings below should be available in most slicers:

- Layer Height: .28

- Line Width: .4

- Wall Line Count: 4 (Critical to strength!) (AKA: Wall thickness: 1.6mm, Perimeters: 4)

- Fill gaps between walls: Everywhere

- Enable Retraction: True

- Retraction Minimum Travel: 3mm (Changed from 1.5mm, made a huge difference!)

- Disable skirts, rafts, etc to fit more parts on the build plate.

Primary Design Considerations:

A lot of thought went into this feature driven design. It has been labeled as "Pretty", but the geometry in this design was carefully chosen with functionality and the manufacturing process (3D Printing) in mind (Form follows Function). The multiple circumscribing outer loops provide all of the strength in this part, which is why it is important to use 4 perimeters when printing. They are also key to the bendability of the tabs themselves. Notice how the tab geometry is designed such that the bending actually occurs not at the base of the tab, but is distributed over the length of the much stronger adjacent perimeters. This is key to the strength and reliability of the design. Also note how the gap between the tab and the perimeter are not concentric; this helps retain mask straps of different sizes. As the tab is bent outward the gap between the tab and the perimeter remains smaller or "tighter" than if the perimeters were concentric. The acute angles between tab sections on the outer perimeter of the part indicate the best location for cuts to remove any unused tabs. The holes in the tabs provide multiple uses including: Looping and locking a mask loop onto the strap, fixturing with hair accessories (Pens, Chopsticks), hanging straps from peg hooks, and whatever other creative uses you come up with!

Recommendation: Print using rainbow spools of filament! This way every batch is a different color. While color may be the least of anyone's worries, providing options can make the user experience that much more delightful!

Features:

• Easy to install! Use your finger to bend out your preferred tabs (Don't forget this!). Bending your desired tabs outward is a core part of the design which makes it easier to install without having to feel for the correct position each time or getting caught on undesired tabs.

• Tangles Begone! Many of the other strap designs have external tabs which can act like a comb and get tangled up in longer hair. My fully enclosed internal tab design and smooth outer perimeter minimizes the chances of hair getting tangled up!

• Strap Agnostic! The tab geometry is designed to accommodate and retain straps of all different shapes and thicknesses!

• Lock one side in place! The holes in the center of the tabs allow you to lock the mask strap in place on one, or both sides. Feed the mask strap through the hole and pull the loop over the tab to lock the strap in place. Then just hook and unhook the opposite side when installing/removing the mask. The locked end will remain attached to your mask!

• Double it up! Prefer to wear it over the head instead of behind the neck? Print two and link them together by inserting their tabs into each other! The tabs lock in place so they wont fall apart on you. This provides 7 additional levels of length adjustability! Be sure to check out the PDF in the downloads section for instructions on how to connect them.

• Cut to length! Once you find your preferred tabs, cut the rest off so the strap doesn't stick out. You can use normal scissors to make the cuts and use fingernail clippers or a nail file to sand/trim down any remaining sharp edges. The acute angles around the perimreter, between the tabs, indicate the best spots to make your cuts.

• Anchor it down! The top and bottom tabs in the center of the strap allow you to attach a hair tie and keep it centered. Use it to put up a pony tail or attach it to another piece of PPE, anchoring the mask strap in place!

• Share it with the world! These straps are a very simple way to make life a little easier for a lot of people. If the masks are easier to wear, the more people will wear them; which is better for everyone in times like this. I give these away free of charge and have received several donations for materials.