Dust level (first X) 0: no protection; 1: prevent large solid invasive; 2: prevent the ingress of medium-size solid; 3: prevent the ingress of the small solid; 4: prevent objects greater than 1mm solid into; 5: prevent the accumulation of harmful dust; 6: completely prevent dust from entering; Waterproof level (X) 0: no protection; 1: water droplets trickle into the shell had no effect; 2: when the housing tilted to 15 degrees, the water droplets trickle to the housing no effect; 3: water or rain...