BUY 4 GET 5TH 70% OFF | CODE: END003 BUY 3 GET 4TH 50% OFF | CODE: END002 BUY 2 GET 3RD 30% OFF | CODE: END001
For example, Buy 3 and get the 4th free. Please notice that the item with the lowest price will be free.
You will get the best price if you buy a multiple of 4.