It's neat framing hammer with a built in clip holding nails. Sort of great idea. Especially for people who don't want to deal with a nail gun. I'd use it since I'm also a super for an apartment buildings. Though I'd probably try to figure out how to use other types of nails in the same tool. Too bad it ain't coming to market.
Michael Young ... his portfolio is here :
www.coroflot.com/michaelyoung