Rab have upgraded all their brilliant sleeping bags for the 2014 season with Hydrophobic Down. This flurocarbon free treatment was developed in conjunction with Nikwax & although Hydrophobic Down is not waterproof it dries much faster, absorbs less water & retains loft far better than untreated down. The Neutrino Endurance 400 is a lightweight all mountain sleeping bag that is capable of shrugging off rain, heavy tent condensation or snow thanks to the Hydrophobic Down combined with the Pertex Endurance outer fabric. This fabric has a highly durable & water resistant PU coating making it perfect for damp or wet conditions. The lining is ultra-lightweight Pertex Quantum, which allows the down to reach its maximum loft in the narrow tapered inner shape. The hood & collar are lined with Pertex Endurance as these areas are prone to getting wet. Access is via a 3/4 YKK zip with an anti-snag baffle. An internal shoulder baffle helps to maximise warmth provides. Both the hood & the shoulder baffle have drawcords. Rab have hand filled this bag with 400g of 800 fill power Hydrophobic Grey Goose Down for maximum loft & insulation in a Tapered Mummy shape which is optimised for bags with fill weights between 100 & 600g. This bag has been designed purely for performance with a close fitting & tapered shape with little slack in the inner. The shape of the Trapezoidal internal baffle chamber delivers a very stable structure that results in a consistent distribution of down throughout the bag & the minimal differential cut combine to give a close technical fit. Differential cut is a technology developed by Rab to ensure that the space between the lining & the outer fabric is optimised for the specific filling & fill power. This maximises the potential of the down to loft naturally resulting in greater performance. Temperature ratings are used to indicate a bags performance but are subjective & can be hugely affected by many factors such as your health & metabolism, how much you have had to eat or drink, how active you have been, humidity & altitude, the type of shelter used & whether you are using a suitable insulating mat. Your sleeping bag is only as good as the mat thats beneath it, we recommend EXPED mats for comfort & insulation. The Comfort rating indicates the range at which a woman gets a full nights sleep, the Limit of Comfort rating indicates the range at which a man gets a full nights sleep & the Extreme rating indicates a range at which a woman is protected from hypothermia. The Extreme rating is basically a survival rating & it is not advisable to rely on this for general use. Pertex Endurance outer fabric Pertex Quantum inner fabric Pertex Endurance inner fabric in hood & collar 800FP European Goose Down Rab fluorocarbon free Hydrophobic Down developed in conjunction with Nikwax enhanced close fitting neck baffle design Mummy taper shape Proportionally assigned differential cut Internal YKK 3 coil zipped stash pocket ¾ length YKK 5 coil main zip Left & right hand zips available Anti snag zipper webbing tape Internal collar & hood drawcord Trapezoidal baffle chamber design Angled foot box Dry bag compression stuff sack Cotton storage sack Temperature tested to new European standard EN13537: 2012 Hand filled in Derbyshire UK