I ordered something from japan, what do these mailing options mean?

Question:

When I ordered my gundam model the mailing option gave me 3 options. Something air (3-5), the next being (5-7), then an option saying (25-30). The options didn't mention what do the numbers mean, days or weeks. I chose the 5-7, what does it mean? It didn't even say what is it, days or weeks.

Answer:

I think it's days.