No its probaly a shot hammer or something. They literally put some weight inside the head. Uf you shake it and it sounds like little beads in there...then it is. I can remewber the name of it, been years since I worked on cars for a living.
Edit....hbmm..crap just had it on the tip of my tongue..nm. lol
edit dead blow lol
http://buy1.snapon.com/catalog/item....re&dir=catalog
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