Graphic Controls 30735489-007 Replacement Chart Recorder Pen for DR4300, purple, channel 1, 6/pk Go to amazon.com Related posts Thing need consider when find chart recorder? FeatureProduct Type: chart recorder penQty/pk: 6Color: PurpleModel: 30735489-007Manufacturer number: 30735489-007 DescriptionScience-lab-data-management-equipment. Made in United States. 8066192 Series product. Color: Purple. Cole-parmer brand items.