How to transfer a material to another. But uom's are different. 
Source material is kg, destination material is mt2.

T. Code MB1B will allow you to transfer material to material. However the base has to be the same. There is no two way about this.

Work around solution: Create destination material with same base unit and same moving average price (MAP), then write off the balance from the source material and write on the balance to the destination material.

Material X has base unit "ea" - each, quantity 5, moving average price $11.00
Material Y has base unit "bt" - bottle, quantity 2, moving average price $10.00

In the above scenario, the system will not allow you to transfer the quantity of material X to material Y because the base units are different.

Option 1.
Use t. code MR21 to change the MAP of material Y to $11.00 if necessary.
Create the physical inventory document MI01 or MI31 with only material X and Y. 
Enter the count for X as zero and the count for Y as 5. View the variance report with MI20 and post the physical inventory document (variance) with MI07.

Option 2.
If it is ok to create a new code, then do so, material Z, with the base unit as "ea" and the moving average price or standard price at $11.00.

Create physical inventory document using t. code MI31 or MI01 for material X, material Y and material Z. Enter the count for material X has zero and the count 
for material Y as zero and the count for material Z has 5 + 2. When you run the variance report (MI20), you will see the amount of 5 being written off from material X 
and the amount of 2 being written off from material Y. You will see 7 being written on in material Y

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