-1 TO -7°C
A 3 to 4 season ultralight sleeping bag designed for minimum weight (only 850g!) & maximum versatility, the Helium 450 has proven popular with hikers in a range of climates from coastal walks to sub alpine elevations. The 450 allows temperature regulation with dual zippers & offers incredible warmth-to-weight thanks to 800+ loft down. Maximise your pack space with a compact, lightweight and versatile Helium 450 sleeping bag.
Ultralight shell fabric and high-loft down fill on the Helium bags mean higher performance for less weight. Durable 10 by 10 denier, 520 thread count Nylon weighing only 26g/m2 with a hot-rolled-cire treatment to prevent down leakage and increase durability. Premium 800+ loft white down fill with DWR Loft treatment adds greater resilience, higher loft and better warmth in damp conditions.
Intended use: Bushwalking, alpine
Season rating: 3 Season
Women &/or cold sleeper: -1°C
Men &/or warm sleeper: -7°C
Shell fabric: 520 thread count, 10 x 10 denier ultralight Nylon (26g/m2)
Lining fabric: 520 thread count, 10 x 10 denier ultralight Nylon (26g/m2)
Standard size weight: 450g fill, 850g total
Women's size weight: 450g fill, 835g total
X-Large size weight: 550g fill, 1000g total
Packed size: 15 x 31cm*
Down rating: 800+ loft premium white duck down
Down treatment: Water resistant DWR loft treatment
Zip side: Left (LHZ) or right (RHZ) on Standard (STD), left on Women's (WMNS) and XL
Zip configuration: Side & foot zips, YKK brand zips, dual sliders on side zip
| Womens / Small | Standard | Extra Large | |
| Max. user height | 170cm, 5"7 | 185cm, 6" | 200cm, 6"6 |
| Internal shoulder circ. | 160cm, 63in | 160cm, 63in | 170cm, 67in |
| Internal hip circ. | 132cm, 52in | 132cm, 52in | 142.5cm, 56in |
| Internal foot circ. | 115.5cm, 45.5in | 115.5cm, 45.5in | 121cm, 47.5in |
*can be compressed smaller using compression sack
Contact us within 30 days of receiving your goods to request a refund or exchange if products are eligible (see: Return Policy).
All packaging or products must be in their original, re-sellable condition.
Outlet sales are final and can only be returned for exchange. Items found faulty or under warranty will be replaced or refunded.
Some special condition products are labelled as No Refund & Exchange Products. Sale of these items are final and are not eligible for neither refunds nor exchanges.
For safety reasons, K2 cannot accept returns on climbing equipment, socks, underwear and some other products unless faulty.
Please check out our refund policy if you need more information.
Bust: Take measurement around the fullest part of the chest, just under the arms and across the shoulder blades.
Sleeve: With elbow bent, measure from centre back of neck (at C7 vertebra) to elbow and down to prominent outside wrist bone.
Waist: Measure around the smallest part of your waist (natural waistline).
Hips: Stand with feet together and measure largest circumference at hips.
Inseam: Measure a pair of well fitting pants from crotch to bottom of leg.
Next to Skin Fit: Designed to be worn next to skin. Body hugging fit for thermal and moisture management.
Active Fit: Trim fitting garments, ideal for active pursuits. Designed to fit over a base layer as required.
Regular Fit: A classic comfortable cut. Designed to fit over base and mid layers without restricting movement.
Relaxed Fit: A generous and relaxed fit. Cut loose enough for layering.
Measurements refer to body size not garment dimensions.
| Size (cm) | 8 | 10 | 12 | 14 | 16 | 18 |
|---|---|---|---|---|---|---|
| Bust | 82-85 | 87-90 | 92-96 | 98-103 | 105-111 | 114 |
| Sleeve | 75 | 77.5 | 80 | 82.5 | 85 | 88 |
| Waist | 68 | 73 | 78 | 84 | 92 | 102 |
| Hip | 90-93 | 95-98 | 100-103 | 105-110 | 112-118 | 122 |
| Inseam Leg | 78 | 80 | 82 | 84 | 85.5 | 85.5 |
Measurements refer to body size not garment dimensions.
| Size (cm) | XS | SM | MD | LG | XL | 2XL | 3XL |
|---|---|---|---|---|---|---|---|
| Chest | 89-92 | 95-98 | 102-106 | 110-114 | 118-122 | 126-130 | 134 |
| Sleeve | 82 | 84 | 86 | 89 | 92 | 95 | 96 |
| Waist | 76 | 80 | 86 | 94 | 102 | 108 | 118 |
| Hip | 89 | 94 | 100 | 108 | 116 | 124 | 130 |
| Inseam Leg | 82 | 82 | 84 | 86 | 88 | 90 | 90 |
Measurements refer to body size not garment dimensions. Wearing ease alters depending on style and fabric.
| Size (cm) | XS | SM | MD | LG | XL | 2XL | 3XL |
|---|---|---|---|---|---|---|---|
| Chest | 89-92 | 95-98 | 102-106 | 110-114 | 118-122 | 126-130 | 134 |
| Sleeve | 82 | 84 | 86 | 89 | 92 | 95 | 96 |
| Waist | 76 | 80 | 86 | 94 | 102 | 108 | 118 |
| Hip | 89 | 94 | 100 | 108 | 116 | 124 | 130 |
| Inseam Leg | 82 | 82 | 84 | 86 | 88 | 90 | 90 |
| Size (cm) | 3XS = 6 | 2XS = 8 | XS = 10 |
|---|---|---|---|
| Chest | 77-80 | 83-86 | 89-92 |
| Sleeve | 78 | 80 | 82 |
| Waist | 68 | 72 | 76 |
| Hip | 77 | 83 | 89 |
| Sleeping bag size | Women's | Standard | Extra Large | 2 Extra Large |
|---|---|---|---|---|
| Maximum user height | 170cm | 185cm | 200cm | 200cm |
| Maximum user shoulder circumference | 160cm | 160cm | 170cm | 176cm |
| Expedition fit sleeping bag size | Small/Medium | Medium/Large |
|---|---|---|
| Maximum user height | 185cm | 200cm |
| Maximum user shoulder circumference | 160cm | 170cm |
| Size | SM | MD | LG | XL |
|---|---|---|---|---|
| Maximum Circumference (cm) | 56 | 58.5 | 61 | 63 |
Measurements refer to body size not backpack dimensions.
Measure from your C7 vertebrae down your spine to the point level with the top of your hipbones, the iliac crest. The C7 vertebrae is the one that sticks out prominently at the back of your neck when you tilt your head forward.
| Harness Size | Extra Small | Women's /Small |
Medium | Large |
|---|---|---|---|---|
| Back Length | 35-45cm | 40-50cm | 45-55cm | 50-60cm |
Using a combination of different layers is the best system for staying dry and keeping warm in winter, or comfortable in summer. Below is a simple guide to the different layers and garment types that can build a great layering system for a wide range of adventures.
Base layers and Next to Skin: This is your first layer and it should be a layer that wicks moisture away from the skin and drys quickly. Polartec Power Dry® garments are the perfect first layer, keeping you dry and comfortable in a wide range of conditions. We do not recommend merino as a base layer as it will absorb up to 30% of its weight in sweat, will become heavy and is very slow to dry.
Fleece & mid layers: A perfect second layer should be a warm, mid weight fleece garment or similar. Something with good stretch and moisture management is ideal.
Insulation layers: In colder conditions and for snow and alpine sports, a warm insulation layer is a great idea. Depending on conditions and how much you feel the cold, consider another fleece layer or a synthetic or down insulated garment. Garments in this category may have a hood, and also be wind & water resistant to delay the need to put on your shell jacket in cold windy conditions. When purchasing insulation layers ensure the sizing and fit allows for a base layer and lightweight mid layer underneath.
Shell Jackets: This waterproof, windproof and breathable layer is your essential piece of gear. It will keep you dry when the heavens open up, or shield you from blizzards in alpine winter conditions. Wear it over a single layer in mild weather or layer up in extreme cold, this garment should always find a place in your backpack. When choosing a shell jacket for bushwalking, trekking, ski or alpine climbing always ensure the fit and sizing allows for a base layer and some mid layers underneath, this way you can use it on adventures all year round.
Insulated Shell & Belay Jackets: If you're heading to Antarctica or have an alpine climb in mind, then it is common to have a very warm insulated outer layer. You can wear it at a high camp or over your shell jacket and other layers whilst on a frigid belay or an unexpected bivy. This is a specialist piece of gear for those who feel the cold or are heading to the high mountains. Ensure the fit allows for multiple layers to be worn underneath.
