riso cylinders

[BPU]

does the E9 drum (S-2623) work in the MZ1090 riso duplicator?

[jermyth]

No, only S-5257 will work.

Yet a S-4714 (MZ790) can be "upgraded" to the S-5257 with the upgrade kit S-5258. But I would not waste time upgrading unless the drum is new or someone else cleaned out all the ink. It easy, but can be messy.

Good luck.