Some devices have pin headers that cannot connect directly to Grove connectors on the Raspberry Pi and Arduino. The Grove to Female Jumper ( for Male Pin Headers) Cable Converter has a Grove connector and feeds to 4 Pin 2.54 female jumper wires. For all Grove users (especially beginners), we provide you guidance documents. Please read our Grove tutorial on http://www.switchdoc.com/2016/02/tutorial-intro-to-grove-connectors-for-arduinoraspberry-pi-projects/ With this converter cable, you can easily connect all of Grove modules to any 2.54mm pitch and non-Grove devices to Grove base boards. 5 cables are included in one pack. Length of each wire is 20cm. Note: The Grove side uses buckled connector.