The second piece of the the Ultrachange is an insulation layer to keep you warm when comes the low temperatures. It has a less-fun dark green colour with patches of black. It weights 340g (12oz) so still lightweight. The face fabric also comes with a DWR treatment called Omni-Sheild to protect you for the odd shower.
The insulation material is synthetic and quite thin but paired with Columbias Omni-Heat technology managed to keep me warm in below zero temperatures with just a long sleeve merino baselayer underneath and the shell on top.
Omni-Heat is a special layer of breathable fabric where tiny metallic dots (disco!) are printed on. The dots act as little mirrors and reflect body heat back while leaving moisture and extra heat escape through the fabric. They feel a bit clammy though and are not very comfortable worn with short sleeves as the dots stick to the skin.
The black patches I was talking about earlier are areas where instead of the synthetic insulation and its face fabric they have put a single layer of very stretchy and breathable fabric with Omni-Heat. You’ll find them on the underarms, hip-sides and neck. They leave great freedom of movement and evacuate perspiration a lot better than the insulated parts.
