I'm wondering if it's possible to put multiple quantity fields on one line item?

I hire tech equipment, and I hire it by the day. I'm hiring out 4 speakers for 3 days. Ideally I would like to be able to put in the price for a speaker, and then put "4 items" in one quantity field, put "3 days" in a second quantity field, and have it laid out nicely to show the customer how that has been worked out.

Currently I workaround this by just setting the quantity to 12, and then explaining the breakdown in the item description, but this isn't very clear or tidy.

Is this possible, or an idea for the roadmap?

Thanks,
PJ