Rab Ascent 300 - Atomic Left Zip Sleeping Bag | Lightweight, Packable Down for Mild Conditions

Overview

The Rab Ascent 300 - Atomic Left Zip is a lightweight, packable down sleeping bag designed for regular use in mild conditions. Updated this season with recycled materials, it serves as an approachable first down bag—ideal for spring camping or summer bothy trips. With thoughtful construction and easy handling, it aims to help you stay warm without carrying excess weight.

Key design features

• Shell and lining crafted from recycled materials: 30D Recycled Pertex Quantum (50gsm) with fluorocarbon-free DWR; Lining: 20D Recycled Nylon (38gsm).
• 650FP RDS-certified European goose down with Nikwax fluorocarbon-free hydrophobic finish to help loft and warmth while keeping bulk down.
• Trapezoidal boxwall construction with differential cut to maximize loft and even warmth distribution across the bag.
• 3-dimensional shaped neck collar to seal in warmth, YKK 3/4 length main zip with a down-filled baffle, plus an internal stash pocket for small essentials.
• YKK anti-snag zip insert and anti-snag internal zip guard; angled foot box for a more relaxed sleeping posture.
• Left and right hand bags can zip together, enabling a wider sleeping setup; comes with a cotton sack with water-resistant base for home storage.
• Garment weight: 840g (Regular) and 895g (XL), with a compact form designed for efficient packing.

Designed for practical warmth, the Ascent 300 balances lightweight performance with durable materials. The 3D neck collar and down-filled baffle work together to minimize drafts, while the 3/4 zip provides a controlled ventilation option without sacrificing core warmth. The left-right zip compatibility adds versatility for solo adventures or shared trips.

Real-life use and sustainability

Whether you’re setting up beneath pines after a long walk or swapping stories at a bothy, this bag aims to deliver reliable comfort on mild nights. Its compact pack size and weight make it a sensible choice for hikers who value space in their rucksack. The updated recycled fabrics and hydrophobic down finish reflect a focus on sustainability without compromising performance.

• Eco-conscious materials support lighter packs while reducing environmental impact.
• Lofty down and trapezoidal construction help you stay warm when nights stay cool, yet your bag remains easy to pack away.

Care, storage, and fit notes

To maintain loft, store the bag in its cotton sack with a water-resistant base when not in use. Available in Regular and XL to accommodate different heights and preferences, with a practical left-zip configuration for easy access and pairing with compatible Rab bags.