1) The cords are high quality. The material has a nice feel to it. This will not snag on clothing. This will not snap, break, or fray.
2) The ear loops are nonslip and rubbery. They will grip the temple arms of the glasses without scratching them or falling off.
3) The ear loops can be adjusted to fit any size temple arm perfectly.
4) There is another adjustment on the cord itself to adjust the length of the cord on the neck. This allows the glasses, when hanging around the neck, to hang higher or lower.
5) The color choices are good, especially if you have a black, brown, and blue set of glasses. The blue cord also matches well with gold and silver frames.