1. Full aluminum material, protection for motherboard. 2. The upper surface of the shell 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. 30 x 30 cooling fan better passive cooling. 5. Simple design, standard screw, easy installation Product name: aluminum protection case Accessory Type: Cases Compatible With: for Orange Pi 4 /4B/4 Applicable product: for Orange Pi 4 development board Purpose: heat dissipation protection Fan: 30 x 30mm (5V) Product size: 91 x 56 x 23mm color:Black Material:aluminum Package Contents: 1 x metal case (upper and lower covers) 1 x cooling fan 5 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 a little different from the real thing. The measurement allowed error is +/- 1-3cm.