1. We designed the housing for installing the 3.5 inch touch screen. When using the screen, remove the cover. The cover can be fitted with a cooling fan (the fan is not included), so you can use it with the cooling fan when you are not using the screen. 2. Dual use: The chassis supports the installation of a 3.5 inch touch screen, and the cover and fan need to be removed for this use mode. (3.5 inch screen and fan cannot be installed at the same time); When the 3.5 inch touch screen is not used, it is generally a chassis with a cooling fan. 3. Support cooling fan: You can install a cooling fan on the cover plate to achieve the cooling effect and extend the service life of for raspberry pie. 4. Bottom hanging hole: We have punched 2 holes at the bottom so that you can hang the chassis or other things. This design is very convenient when using the 3.5 inch touch screen. 5. How to assemble the screen and shell: 1. Install for raspberry pie on the substrate; 2. Correctly insert the 3.5 inch touch screen into the raspberry pie through the GPIO pin (do not misplace it) 3. Install the cover plate Product name: chassis shell Material: metal Colour: Black Specification: separate metal shell Scope of application: for 3B+/3B Package Contents: 1 x Metal shell 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.