The VBD- 2 has a 2" aperture diameter within a 2.5" diameter outer shell. Length is approx 4.2".
This unit can be mounted horizontally by using a standard laboratory post or other fixturing with the 1/4-20 Tapped hole in its body.  
Finish is Black Anodized.
 
The unit is non-water cooled and has a rating of 200 Watts maximum energy.