Eathtek Replacement CPU Cooling Fan for Dell Inspiron 15R 17 17R 3521 3721 5521 5535 series, Compatible part number 5721 74X7K 074X7K DFS470805CL0T (Not fit for N5010 N5110 N7010 N7110 Series) Not fit for N5010 N5110 N7010 N7110 Series laptop! Compatible Model Numbers: Dell Inspiron 15R 17 17R 3521 3721 5521 5535 Replacement and high quality,Replace your faulty, cracked or broken fan. Each fan is tested before shipping All pictures are taken from the real item, please check carefully before bidding. Notes: The fans are produced by Forcecon,ADDA,Sunon,Kipo or any other manufacturers,you may receive any depending on the stocks.