How you sell the pen should depend a bit on the job and what sort of person they are looking for.
Watch a few adverts and think about the different kinds of messages. What messages about the pen are going to best reflect the kind of person they are looking for, for this job specifically.
Don't try to do all of these - they are different angles to take. Pick one (or two very similar and related ones) and run with it, putting in more detail etc.
Budget conscious - this pen is the best value for money available, it's surprisingly cheap and still does the job.
This pen is really high quality with every component engineered to perfection. It may cost a little more but that gives you the confidence that you are buying the best.
We've done some extensive market researve and found that 95% of people who own this pen are deeply satisfied and fundamentally fulfilled by owning this pen, and owners of other kinds of pen reach only 52% at best.
You didn't think you needed another pen, but you're wrong, you need this pen. Other pens are inadequate.
This pen is a pen for people who are sophisticated, elegant and have their lives totally sorted. When people see you using this pen they will admire and envy you.
This is the pen that (insert celebrity name) always uses, because it's the pen that most comprehensively expresses why he/she is so wonderful. You should use the same pen as a way to feel special like that.
These beautiful people chose to buy this pen on the same day as each other and it's caused them to fall in love. They are probably shagging right now. If you fancy a shag you should buy this pen.
This is not just a pen. It may look like a pen and yes you can write on paper with it but it's also a flashlight a calculator, a ruler, a handy spanner, a USB memory stick and an emergency dusresss beacon
There are other angles you can take obviously. Remember they don't actually need you to sell the pen, they are trying to find out what kind od person you are.