Header and cable kit for ARM JTAG SWD and Arduino Zero JTAG legacy (2x10 pines, 2.54mm) to SWD (2x5 pines, 1.27mm) adapter 6" 10-wire 1.27mm cable (SWD) 6" 20-wire 2.54mm cable (legacy) JTAG legacy to SWD adapter also has a 12-pin breadboard friendly header Makes it easy to program and debug cortex-M (SWD) devices using legacy (JTAG) programmers and debuggers like J-Link, Realview.