Charles Ellicott Commentary Numbers 3:26

"and the hangings of the court, and the screen for the door of the court, which is by the tabernacle, and by the altar round about, and the cords of it for all the service thereof." — Numbers 3:26 (ASV)

And the hangings of the court ... — See Exodus 27:9 and Note.

And the cords of it for all the service thereof. —The pronominal suffixes do not seem to refer to the court, whose cords appear to have been under the custody of the Merarites (Numbers 3:37), but to the mishkan or Tabernacle itself. Or, the latter suffix (its service, or the service thereof) may be designed to refer to each of the various things mentioned, as in Numbers 3:31, because the words for all the service thereof may mean for everything that had to be done in connection with the things mentioned.