Stackable 0.100″ Female Header: 2x20-Pin, Straight

This stackable 40-pin female header features two rows of 20 pins spaced with a 0.1″ (2.54 mm) pitch. The extended pins allow multiple units to be stacked as popularized on Arduino shields. The 2×20 size is notably used on the Raspberry Pi Models A and B as well as the Raspberry Pi 2 Model B.