Summary Recently, Brook from Printrbot launched a campaign to put 3d printers in classrooms called Adoptabot. Printrbot put together some hardware kits that they offered a limited number of and sold them through their website to kick off the campaign. You can find out more about adoptabot here: https://www.adoptabot.org/ . Or by visiting Printrbot's website (https://printrbot.com/) In the kit they included a delrin z nut. For anyone that is looking to piece together their own Adoptabot, this is a printable replacement for the delrin z nut.