Stratasys J850 Manual page 37

3 Materials
Both sections of each print head are loaded with the same material.
Up to three Model materials are available, with high-speed printing.
Single Material
Both sections of two print heads are loaded with the same Model
material—DraftGrey (RGD750).
Both sections of two print heads are loaded with Support material.
This mode produces build trays with DraftGrey material, in Super High
Speed mode, at a layer resolution of 55 microns.
5. In the Required materials section of the wizard screen, select one or more
replacement materials cartridges.
6. For Model materials, select
cartridges.
Loading one replacement cartridge is more economical because it
potentially requires less flushing of material currently in the system.
However, when one cartridge is not sufficient, loading two cartridges
enables continuous printing until the print job is completed. When one
cartridge empties and the other one is being used, you can replace the
empty cartridge with a new one.
if you need to load two replacement