int Led01 = 6;
int Led02 = 9;
int Led03 = 5;
int Led04 = 3;

int del = 500;
int Low = 5;
int mid = 10;
int high = 15;
int vhigh = 255;

void setup() {
  // put your setup code here, to run once:
pinMode(Led01, OUTPUT);
pinMode(Led02, OUTPUT);
pinMode(Led03, OUTPUT);
pinMode(Led04, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
analogWrite(Led01,Low);
delay(del);
analogWrite(Led02,mid);
delay(del);
analogWrite(Led03,high);
delay(del);
analogWrite(Led04,vhigh);
delay(del);
}