it's just a cheap, popular form of insulation that's easily done, it's camping mate cut to size, stuck onto the keg/MLT with a decent glue and then a roll of '100mph tape' wrapped around the mat.
depending on the time of year but the mash generally loses 1 degree over 60 minutes.
camping mat http://www.amazon.com/Foam-Camping-Mat- ... B001BSI5UW
100 mph tape https://www.ibmilw.com/item/view/id/105109
Dave
