Cosy warmth when the cold kicks in the womens shimmer flash jacket utilises columbias unique omni heat technology synthetic insulation with a foil like liner to reflect heat back for incredible warmthwinter warmth neednt be bulky the womens shimmer flask jacket from columbia is packed with 100g of omni heat insulation in a lightweight super sleek design for style and protection in bitter cold the reason its able to achieve such levels of warmth is the omni heat lining it reflects