Does size matter?

Now that I have your attention

I'm finishing two smaller size bowls/shaving soap bowls. They are actually for a lady who wanted wholesale and then backed out. They are tightly 3" across in the internal measurement. I have an Edwin Jagger refill that would fit perfectly.

But if you could let me know, when I list it for sale how could I most acurately demonstrate/communicate that they would require the more diminuative soap puck? Besides showing the Jagger soap with it, because I have the soap for research. But I don't want to confuse the issue with soap to go with it. I guess I could shoot the pictures before I use it. But anyhoo, what are your thoughts? Thanks a million. K ps I'm pretty dyslexic so if you all could overlook my spelling issues, I would thank you.