[Grammar] Omission of relative pronouns?

[BOSS12345]

Hello,

I'm an international graduate student studying in US.
I was reading a weekly research report of one of my friends and got a question.

My friend wrote that

"Double side polished glass wafers substrates 3 inches in diameter and 550 microns in thickness were purchased from company ABC."

I would correct the sentence above like "Double-side-polished glass wafer substrates, 3 inches in diameter and 550 microns in thickness, were purchased from company ABC."

Is my correction right?
Please advise! Thanks!

 

[zjennin]

"Double-side-polished glass wafer substrates, 3 inches in diameter and 550 microns in thickness, were purchased from company ABC."

You did a good job; I just have a few suggestions:
"Double-sided polished glass wafer substrates, 3 inches in diameter and 550 microns thick, were purchased from Company ABC."

-Not a teacher.-

 

[BOS12345]

You did a good job; I just have a few suggestions:
"Double-sided polished glass wafer substrates, 3 inches in diameter and 550 microns thick, were purchased from Company ABC."

-Not a teacher.-

I have another question. I think I can put "which are" as written below.
So, the relative pronoun "which' can be omitted.

Double-sided polished glass wafer substrates, (which are) 3 inches in diameter and 550 microns thick, were purchased from Company ABC.

Now I'm wondering if I can write:

Double-sided polished glass wafer substrates 3 inches in diameter and 550 microns thick were purchased from Company ABC.

Could you please tell me if it is okay or why it is not fine.

Thanks!