Fixed Direct Expense

Dear John Sir, i was getting a little intuitive and just thinking about a cost card where we have variable overheads and fixed overheads. I just thought upon possibility of case of a Fixed Direct expense. Is it possible in real life situation that we have a Fixed Direct expense OR it is absolutely impossible and all Direct expenses are necessarily Variable. i understand that Direct expenses are expenses which can be directly linked to a cost unit and hence this query .. Thanks Amit