PURCHASE ORDER UNIT

HELLO EXPERTS,

In my material master for a finish good i have maintained Unit of Measurement as PC(piece), purchase order unit as DZ (dozen).

So while i m creating a standard PO , It takes the order unit as DZ, but when i m creating a stock transport order using same material, it takes order unit as PC.

Can u tell me what may be reason behind it.

I m working in a hosiery company, and more than 100 STO is done everyday.

So can anybody suggest me what to do, so that I overcome this problem.

Thanks And regards.

Raghu.