7.05 OZ. Just got mine today. Ran just great right out of the box. I kind a laughed when I read where some one said theirs pulled 40 cars up a grade, however, I changed my usual procedure of putting approximately 20 cars on an engine for its first test, and I attached 42 fifty feet plus cars. It took off and went right up my 2% grade and around a 180 degree turn without slipping. Only problem, was an Atlas coupler on about the 6th car kept giving out. Really think Bachmann has done a superb job on this engine. I have most of Bachmann's recent steam locos and really think all of them all great. The pulling power isn't as good on some of them (certainly not as good as on this one) but I still would rate all of them an A.