I can't remember the part number, but it's made by Honeywell and stocked by Digikey. Look in file Platform.h of the RepRapFirmware source code for the part number. Don't forget to get the high temperature heatshrink too.
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
