PCB uses 4 layers of 1mm thickness and 0.3/0.45mm drilling. 

 There are two LCD sockets on the PCB, one is 40P SPI+RGB666+TP. There are many types of this small screen with capacitance touch. Generally, the SPI port needs to be used to initialize the LCD screen chip. 
 The other is an ordinary 40P 4.3" 5" 7" regular TFT screen, which uses a separate 6P TP FPC to connect a capacitive touch screen. 
 Typical screen sizes and resolutions are listed behind the PCB.