This is an offsetting a/c for internally consumed material during manufacturing process and no financial impact rather if it is not posted financial (P&L) a/c will not reflect properly.
Please analyze the whole cycle of manufacturing you will understand. Just I am giving a example..
When you are manufacturing a SFG mat, all primary cost (mat & act) have been absorbed and your P&L a/c has been booked. Now that SFG is going to use by FG ..so a consumption a/c is required, if we define a direct P&L a/c then there will be double booking of expenses for that SFG...but system requires a a/c to off set the stock of SFG..so this a/c is required.
I think you are satisfied...
Please close and reward..