The DS1307 RTC Module is a reliable real-time clock module for accurate time and date tracking in Arduino, ESP32, Raspberry Pi, STM32, and other embedded projects. It uses the I²C interface, includes an AT24C32 4KB EEPROM for data storage, and provides a 1Hz output signal for timing applications. A CR2032 backup battery holder maintains time during power loss; the battery is not included.

The 4×4 Membrane Keypad is a compact 16-key matrix input device featuring numeric keys 0–9, A–D function keys, and * and # keys. It uses an 8-pin row and column interface for easy connection with Arduino, ESP32, ESP8266, Raspberry Pi, STM32, PIC, AVR, and other microcontrollers. Its thin, flexible design and self-adhesive backing make it ideal for password locks, access control, robotics, automation, menu navigation, and embedded electronics projects.

16-channel bidirectional analog and digital multiplexer module for connecting multiple sensors or signals using only four select pins and one signal pin.