For Sale are 4 BRAND NEW COMAIR ROTRON 4.5 INCH ROUND FAN. The fan is 12V (DC) 6.3A , 7.6 WATT and the Model Number is MC12P3. The case is made of plastic and the fins are plastic. The inside measurement is 4.5 inches and thte outside case measures 6 inches from the hole to hole. You will receive all 4 fans as pictured.