When installed on the bottom strap of a mask, allows much increased convenience in installation and removal of mask.
Print with the Clasp standing on it's side to avoid overhang. Print Hook on it's belly for highest strength. Print with 3 to 4 shells and 100% infill as these parts are likely to see high-cycle stress loads.
PETG or ABS is ideal, PLA can work in a pinch.
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