Sales qty conversion to COPA

Dear CO-PA gurus

I have requirement that sales qty and SKU qty is different.

For example, SKU in material master is PCs,

but in sales order, it is sold by Carton (including 12 pcs).

So, as value field for sales qty, I plan to use FKLMG instead of FKIMG

Billed Quantity: FKIMG

Billed Quantity in SKU: FKLMG

Am I correct?

Yoshi