2N2222A by Texas Instruments is a small signal NPN bipolar junction transistor (BJT) with a max collector-emitter voltage of 40V and a max collector current of 0.8A. It is commonly used for switching applications due to its fast turn on/off times (35ns/285ns) and high transition frequency (300MHz).
P-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Power Dissipation (Abs): .5 W; Transistor Element Material: SILICON; Moisture Sensitivity Level (MSL): 1;
PIC18F4550-I/PT by Microchip: 8-bit microcontroller with 44 terminals, 48 MHz clock frequency, and USB connectivity. Ideal for industrial applications requiring low power mode and 10-bit ADC channels.
KSZ9031RNXIC by Microchip Technology is a network interface chip with 1 transceiver. It operates at a data rate of 1000 Mbps and has a nominal voltage of 1.2V. This chip is commonly used in industrial applications requiring Ethernet connectivity.