1. Full aluminum alloy material, well protection for motherboard. 2. The upper surface of the is designed with multiple grooves, which is more conducive to the distribution of hot air. 3.The CPU, RAM and other module positions are provided with silicone thermal pads to make heat dissipation more efficient. 4. 30X30 cooling fan provide better passive cooling. 5. Simple design, standard screw, easy installation Product name: aluminum alloy protection case Accessory Type: Cases Compatible With: for 3 /3B/3 Applicable product: for OrangePi 3 development board : heat dissipation protection Fan: 30X30mm (5V) Product size: 85 X 56 X 22mm Colour:black Material:aluminum alloy Package Contents: 1 x metal case (upper and lower covers) 1 x cooling fan 3 x thermal pads 1 x Screw package 1 x screwdriver Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.