... , finger-pressing, rolling, etc, it most effects on eye part2.A/C and D/C use both ok.3.7 massage ... prevention of near-sightedness: Use 5 minutes once and twice a day for improvement of eye vision, micro-circulation of eye ... . By using PG-2404 Shining Bright Eye Massager, you can easily get a sound sleep.8. Help old people for obstruction of presbyopia ...