Rab Women's Ascent 900 Down Sleeping Bag (-18C)

The Ascent 900 is an exceptionally warm sleeping bag designed with a spacious mummy fit for enhanced comfort. Insulated with 900g of 650FP duck down, it offers reliable warmth in cold conditions while allowing room for additional layers when necessary. Suitable for year-round use, it is particularly well-suited to winter environments similar to those found in the UK, New Zealand, or Scandinavia.

Designed specifically for women, this version is slightly shorter in length, features a narrower fit at the shoulders, and provides extra width at the hips to improve thermal efficiency. The Ascent is crafted using a lightweight yet highly durable recycled Pertex® Quantum outer fabric, paired with a recycled nylon lining. Its trapezoid-shaped boxwall baffles are carefully constructed to ensure the hydrophobic duck down achieves full loft while minimising cold spots. Hand-filled in the UK, each down bag retains its loft and warmth from the outset, as the down has never been compressed prior to use.

The generously sized mummy shape, along with a spacious foot box, creates a comfortable sleeping environment, while the close-fitting neck baffle effectively seals in warmth when temperatures drop. A ¾ length main zip, complete with a down-filled baffle, helps to prevent draughts from creeping in.

Designed with practicality in mind, the sleeping bag includes an internal zippered stash pocket to securely hold essentials such as a phone or headlamp. It also comes with a cotton storage sack for home use and a compression stuff sack to ensure a compact pack size when travelling. For those adventuring with a partner or seeking additional space, a left-zip and right-zip version can be paired together to form a double sleeping bag.

Features

• The outer shell is made from 30D recycled Pertex® Quantum (50 gsm) with a fluorocarbon-free DWR finish for added water resistance.
• The lining consists of 20D recycled nylon (38gsm), offering a soft and lightweight interior.
• Insulated with 650FP European duck down, featuring a Nikwax fluorocarbon-free hydrophobic treatment (1100g / 38.8oz).
• The trapezoidal boxwall construction, combined with a differential cut, maximises loft and thermal efficiency.
• A three-dimensional shaped neck collar ensures warmth is effectively sealed in.
• The YKK ¾ length main zip is reinforced with a down-filled baffle to retain heat.
• A YKK anti-snag zip insert and internal zip guard help prevent fabric from catching.
• An internal YKK zippered stash pocket provides secure storage for small essentials.
• The angled foot box supports a natural sleeping posture for added comfort.
• Left and right-hand zip options allow two sleeping bags to be zipped together.
• A drawcord stuff sack is included for easy packing.
• A zippered storage sack with a water-resistant base ensures protection when stored at home.
• The outer and lining fabrics are both made from 100% recycled polyamide.
• The wide mummy shape balances warmth and comfort with room to move.
  
  

Sustainability Features

• Fluorocarbon (PFAS) free fabric
• Fluorocarbon (PFAS) free product
• Made with renewable energy
  
  

Specifications

Size Guide

Technology

Pertex® Quantum

This lightweight, windproof fabric is designed to enhance insulation by allowing it to achieve maximum loft. Offering exceptional packability and reliable protection, it is perfectly suited for mountain pursuits.

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