These parts can be used together with a Flex3Drive kit to build the Flex3Drive on an Ultimaker 2.Please note that building a Flex3Drive onto an Ultimaker 2 is not an easy task. This is an upgrade for the handy tinkerer.The draft installation manual was made by Korneel Bullens.source code for firmware can be found on:https://github.com/Ultimaker/Ultimaker2Marlin/tree/Flex3DriveWith thanks to Mutley3D who invented the Flex3Drive.