Building on the success of the original Pro SL Prima Loft Jacket this updated version has enhanced breathability & stretch panels for an even better fit. Lightweight Insulation Two different types of Prima Loft fill have been used. 80g of Prima Loft Gold has been used on the front torso maximising insulation exactly where you need it most. 60g of Prima Loft Gold fill has been used on the sleeves cutting down on bulk & 60g of Prima Loft Silver Active has been used on the back giving enhanced breathability & accomodating some stretch to create a great fitting garment. Prima Loft Insulation Prima Loft insulation boasts an exceptional warmth to weight ratio tiny pack size extremely breathable construction & is highly water resistant making it a tremendously versatile performance insulator. Lightweight windproof shell panels with Prima Loft GOLD insulation PFC-Free non-toxic durable water repellent finish Stretch panels on underarm & back for unrestricted movement Triple rear pocket system with zipped security pocket Lightweight internal hem elastic with silicone gripper Ventilation via underarm perforations Subtle reflective details 90 Day Satisfaction Guarantee