Vandersteen M5-HP Crossover Filter

5 ¾" long, 3"wide, 1 ½" deep

Don't know about the heat resistance factor.  Call Vandersteen Audio or John Rutan at Audio Connection in Verona NJ and they can weigh in on that question.

I have mine on Atma monoblocks. The pigtails keep the well away
from the heat-Unless you want to put them on top of the amps, which wouldn't be a good idea.
Bob

all the component parts with exception of the 9v batts are rated for duty inside electrical components, having said that I suspect that the battery will not like high temps and the general life of everything else shorter...the pigtail should in most case keep you far away...

well I learned something 

Duracell Copertop 9v rated to 54 C = 129.2 F

now how hot are those monoblocks ???

Thanks everyone.  I also heard from Richard Vandersteen who advised that heat is not an issue with the M5's.