MP040 is a 4.0 MHz quartz crystal designed for fundamental mode operation with an 18 pF load capacitance, housed in a standard HC-49/U metal package. The crystal features an AT-cut design with a frequency tolerance of ±30 ppm at +25°C and frequency stability of ±50 ppm over the operating temperature range. It exhibits a series resistance of 100 O and a maximum shunt capacitance of 7.0 pF, with drive level capability of 100–1000 µW. The MP040 is ideal for applications in wireless communications, FPGA/microcontrollers, computer peripherals, and consumer electronics requiring stable timing references with proven reliability in commercial and industrial environments.