1. Easy access to all ports Dual Micro- HDMI, audio/video, USB and Ethernet port cutouts, as well as USB-C power connector and microSD card access. Special design makes it easy to insert/remove SD cards. 2. Excellent heat dissipation performance Double cooling Has a strong heat dissipation performance, and the for Raspberry Pi 4 model B board works, no longer worry about overheating. 3. 9-layer acrylic shell designed for Raspberry Pi 4 Model B that does not block the Wifi or Bluetooth signal of the for Pi Make your for Raspberry Pi 4 Model B motherboard safer and better. The transparent case makes it easy to observe the internal state, and the pi board works to check that all electronic components are working properly. Installation method: Start without disturbing the order, take it off from the third floor, place the motherboard on the third floor, and stack the rest one by one. colour:black Material:Acrylic size:The heat sink dimensions are: 14x14x6mm,14x9x5mm,9x9x5mm Package Contents: 2 * for Raspberry Pi 4 Model B 9-layer acrylic shell 2 * cooling fan 6 * black aluminum radiator 2 * screwdriver 8 * screws (shipped without for raspberry pie motherboard) note: 1. This case is designed for the for Raspberry Pi 4. Not compatible with other for Raspberry Pi models. 2. Remove the protective film from the outer casing before assembly. And follow the instructions or videos to make sure it is installed in the right way. 3. This package does not include the for Raspberry Pi 4 Model B board.