My wife bought a Thinkpad Yoga 2 a while ago. I'm a Thinkpad fanboy and have several chargers (the round yellow plug) around, so I bought her this adapter to use.
She didn't like the laptop and returned it... the adapter is useless with her Dell.

Buy me a Cappucino to go and it's yours (or give me the 3$ for it). I work at the VA Palo Alto, I'm on campus maybe once a week.