"First item from both sets" vs "First items from both sets"

Question

I was commenting on a question on Stackoverflow and found myself writing:

You are comparing the first item from both sets

Meaning in this case that the OP was taking an item from one collection, and an item from a second collection, and comparing them, with emphasis on the fact that the comparison was of the very first item picked from each collection.

My phrasing made sense in my head because in each set, you take the first item. But on further thought, it seemed odd because you wouldn't say

You are comparing the item.

Yet when I look at the phrase

You are comparing the first items from both sets

it seems unnatural to me.

Is my original phrase correct, or should I have written "items?"

I've done some googling and couldn't find a clear example that differentiates between the two forms.

Answer 1

Both of the phrases are similar. However, when you say:

the first item from both sets

You refer to the very first item in each set. But, when you say:

the first items from both sets

it can refer to the multiple items at the beginning of each set.

As commented by @Xanne:

A sentence you can consider using is

You are comparing the first item from each set.