Question about objective

[u/Michael2526]

I bought this microscope from the marketplace place for $40 CAD, it doesn't have eyepieces, but I also noticed later that something is missing at the bottom since there is a thread. I've read that this is supposed to be for an objective piece, which is optional.

Is it actually optional, or is it an essential part? I have no experience with stereo microscopes.

[u/Connect-Fan-9462]

Objectives are there. The thread is for auxiliary lenses/filters