which is the correct form ? sometimes, I'm still having trouble using the 'article'.
1) Have we ever ordered THE lock housing for storage cabinet before ?

2) Have we ever ordered lock housing for THE storage cabinet before ?

3) Have we ever ordered THE lock housing for THE storage cabinet before ?

Question

which is the correct form ? sometimes, I'm still having trouble using the 'article'.
1) Have we ever ordered THE lock housing for storage cabinet before ?

2) Have we ever ordered lock housing for THE storage cabinet before ?

3) Have we ever ordered THE lock housing for THE storage cabinet before ?

Answer

The third one is correct.
The lock housing and the storage cabinet, are specific items so you need to use "the"