The Cirrus Flex is one of our most versatile jackets to date. Lightweight, warm, and breathable - this synthetic layer is designed for strenuous days on the mountain. Whether you plan to climb, hike, scramble, or ski, the Cirrus Flex is set to become your go-to jacket.

Lightly filled with Cirrus™ 3M Featherless insulation, the Cirrus Flex offers excellent warmth for its weight. Worn as a windproof outer or versatile midlayer, it is simple yet highly effective. The popularity of this jacket comes from its ability to balance and regulate temperature - keeping you warm when you stop and avoiding overheating when you're on the move.

Designed for active use, the Thermic™ stretch fleece panels offer excellent flexibility and improved breathability, while the durable Hyperlite™ rip-stop outer easily sheds water, allowing it to dry quickly when wet. If you need to drop a layer, the left pocket doubles as integrated stuff sack ensuring it packs away neatly taking up minimal room in your pack or clipped to your harness.

A firm favourite amongst Rab staff, the Cirrus Flex has also proved popular with our athletes and those who have already bought the jacket. Louise Tully, a member of our AMI Test Team, describes:

"I took the Cirrus Flex jacket on a recent ski touring trip to Norway. The weather was mixed, from heavy snow to bright sunshine but the Cirrus Flex coped well throughout. On the rare occasion I took it off, it packed down really small, therefore not taking up valuable space in my bag. I was particularly impressed with the comfort. The stretch panels down the sides give it an unrestrictive feel which made it fantastic to wear. It's a great lightweight insulated jacket which can be used in all weathers and the breathability and comfort allow it to work well even during activity."

Technical details:

• Weight: 360g in men's large / 320g in women's 12
• Available in size S to XXL for men and 8 to 16 for women – slim fit.
• Filled with Cirrus™ 3M Featherless insulation, equivalent to 600 fill power down
• Hyperlite™ rip-stop outer and lining fabric with thermic™ stretch fleece panelling
• YKK® VISLON® front zip with internal storm flap and fleece lined chin guard
• 2 YKK® zipped hand pockets. Left pocket doubles as an integrated stuff sack
• 2 Interior drop-in pockets
• Lycra bound elasticated cuffs and hem drawcord

Available to buy now - visit the Rab website to find out more and read a wide range of customer reviews: