As a matter of note, mine in the photo is an O scale 1/48 K-Line (EP-5 for those unfamiliar with NH's locomotives) three-rail one that was converted to two-rail. I have been told that the K-Line one is every bit as good as the Overland(?) brass one and runs extremely well. I also have a three-rail one that proved itself on a friend's layout. Unfortunately, they both have the same road numbers. Another NH motor that I have, an EP-3, this one a cast bronze beast by Baldwin Model Locomotive Works:
The wire is to hold the lid on as it is separate from the body during shipping; really makes doing an work ion the interior very easy.
Although not NH but an E. P. Alexander cast bronze Pennsylvania GG1:
The drive: