This is the Yeah Racing Aluminum Light Fan Heat Sink Mount suitable for 30 x 30mm and 40 x 40mm Fan. It is made of high quality aluminum which is highly durable and extremely light in weight that weighs 5 grams only. Its unique design allows it to be mounted to the motor firmly and securely. It can be easily installed by using the set screws included. The 3mm washers included can be installed in between the motor and the fan to enhance the heat dissipation effect. Got three colors available, gunmetal, black and blue.