Which is better for intervertebral foramen mirror?

No matter which kind, even the original German products are not particularly suitable for orientals. German designers are products designed according to westerners' physique, with thick outer diameter. It is very dangerous and inhuman for orientals to polish intervertebral joints with circular saws. The intervertebral foramen mirror designed by Professor Chen has an outer diameter of 4.5-5.5 mm, which is suitable for China people's physique and is very convenient to use.