MMBT3904LT1G by Onsemi is a NPN BJT with max. collector-emitter voltage of 40V, hFE of 30, and fT of 300MHz. Ideal for small signal applications in electronics due to its compact size, high transition frequency, and low power dissipation capabilities.
LM555CMX by Texas Instruments is an Analog Waveform Generation IC with 8 terminals. It operates at a nominal voltage of 5V and supports power supplies ranging from 5V to 15V. This versatile IC, housed in a small outline package, is commonly used for pulse and rectangular waveform generation in commercial temperature environments.