Procolored Siphon Circulation refers to the Siphon White Ink Circulation System, an innovative technology patented by Procolored. Procolored siphon circulation was initially applied on Procolored F13 Pro Panda DTF printer (or DTF Pro Gen-2), and so far has been progressively integrated into the rest products. https://www.procolored.com/pages/procolored-strength-of-siphon