●Latest version: 2020 ergonomically designed head strap, high-quality ABS material, enhanced Head Strap support and stability ●Durable 100% injection mold production: all parts of the head strap have not been 3D printed and have a long service life ●Quick installation and adjustment: halo strap is easy to install and disassemble, the rear knob can quickly adjust the size and tightness ●Ergonomic design: The golden ratio of the front and back of the halo strap device is 50:50, and it is comfortable to wear, without squeezing on the face and nose ●The contact surface is soft and easy to clean: The head strap contact surface is made of soft sponge and triangular leather, which increases friction and is easy to clean.