Shield Stackable headers for Arduino (R3 Compatible) - 3Pin, 6Pin, 8Pin,10 Pin Use these to stack shields on your Arduino! These are standard 6-pin, 8-pin and 10-pin 0.1 spacing female headersâ?¦with a twist! The pins are extra long which means you can use these to stack shields! The legs are 10.5mm (0.42â?³) long, so after the PCB thickness (1.7mm/0.07â?³) you have a height of 8.8mm (0.35â?³). Comes in a package of one 23-pin header, 2 x 8-pin headers, 2 x 6-pin headers and 1 x 10-pin header for full compatibility with shields designed for Arduino R3 & Leonardo.