Castelli mortirolo 4 jacketthe mortirolo 4 jacket is a favourite among cyclists because its exceptionally good in a wide variety of conditions this jacket keeps you warm but also vents a lot of moisture out the back thanks to a thermal warmer fabric for added ventilation there are zipped front vents the gore windstopper on the front makes this a great piece for dry fall and winter days featuresgore windstopper x fast fabric on front is windproof and water resistant back in warmer to prev