Replacement part for the head strap holder of the VO2 max test mask. The original strap holders are quite prone to breaking (acrylic) and when they break, it is necessary to buy a whole new mask (very expensive). With this 3D model, you can replace the acrylic parts at almost no cost and protect your investment. Printing recommendation: I printed using nylon. 100% infill, brim adhesion (12mm). After printing, heat the parts with a heat gun or hot water and bend them about 45 degrees at the center. Tested on extra