3D brows use an advanced tattoo technique to create the look of ultra-fine, long lasting hair strokes that blend seamlessly with your natural brow hair - while HD brows are a process which involves a combination of brow treatments, including tinting, waxing and threading.3D brows use an advanced tattoo technique to create the look of ultra-fine, long lasting hair strokes that blend seamlessly with your natural brow hair - while HD brows are a process which involves a combination of brow treatments, including tinting, waxing and threading.