1Infrared Sensor - Put the hand into the machine without pressing timing buttons and it will automatically turn on to work. 2Double light source and 36pcs of LED lights beads, no dead zone, all nails can be dry at the same time. 3LCD display screen for clearly reading the working time. 44 kinds of timer setting: 10s, 30s, 60s, 99s timer. No need to worry about black hands. 5New flame retardant material, safer, stronger and more resistant to fall.