Dont need to be heated , living up here ,,
. Na mate they are a rolled allimunium about 150mm long , painted matt black inside ( even tho the photo dont show this ) , so they weigh nought and work well .
They just push on and off , using velcro on the inside and nothing but the bino bodies on the out side( slide on about 25mm ) , this is a great set up , easy to use and give awsome images .
.
I love using them .
Pm me your e/mail and I will send you some more photos of the build , if you want .
Brian.