header, dual row, pass-thru, 50-pin

This is the header we use for the -FM and -FM1 connector options on our Adapt-series MCU, application, and accessories products.  It is a quality stackable header at about half the price of the Samtec part we used to use.  Unlike the stackable headers commonly used with Arduino, these pins are square (not rectangular). two rows of 25 positions 0.1-inch (2.54mm) centers 0.025-inch (0.64mm) square pins high-temperature black plastic receptacle gold-plated contacts and pins