An expert look at the latest in outdoor gear.

Therm-A-Rest takes a comfort-first approach to backcountry nights with the convertible Boost 650 sleeping bag.

Versatile is a word we at Wilderness like applying to outdoor gear. Such products are adaptable for different conditions and hold appeal because they provide value for money and are less likely to sit on the shelf, to be used only a couple of times a year. It will be functional outdoor gear that’s better for the environment, too. Therm–Rest’s new Boost 650 sleeping bag embodies this concept. It has a suite of features making it well suited to tramping, camping and travel – as well as being a pleasure to sleep in. 

The most notable feature of this 0°C (limit) rated bag is its centre-top WarmZip, which converts it from a relaxed semi-rectangular shape to a thermally efficient mummy fit. There’s a roughly 6°C difference between the two modes, providing summer comfort and freedom of movement, while also ticking the box for cooler shoulder season use. This functionality would also be appreciated by travellers who experience a range of climates.

The bag’s practical aspects continue with two zip-opening arm holes. Most trampers would agree that reading while in a sleeping bag can be awkward when you’re also trying to keep warm. Also cooking or using a phone are easier when you can stay in your bag and be arms-free. This bag comes in a size for everyone, with each of the three lengths also available in traditional and wide dimensions. 

While its comfort-oriented features are aimed at entry level to intermediate users, it’s not without high-end details, such as zoned insulation, a full hood, neck baffle and silky smooth 20D nylon fabric.

Key features we like

Convertible comfort

There are six different sizes to choose from, then, with the WarmZip, you can toggle between two modes: roomy semi-rectangular shape for warm nights, or zipped closed for a snug mummy-fit and a 6°C difference in warmth. The main zip is full-length so you can open the bag to the feet, but not completely flat like a quilt. 

Zoned insulation 

This bag makes the most of its 650 fill-power down with differential fill; meaning the down is zoned so there’s more where you need it (core, shoulders and feet), and less where you don’t (the underside of the bag). The down isn’t top-of-the-range for fill power, but it is water resistant and is RDS-certified for happier geese. 

Hands free reading

Two zip-up arm holes may seem gimmicky, but they make life in bed much easier for reading, playing games, preparing food or doing any other in-tent task. They also provide ventilation. The weight addition is negligible and the zips are baffled so they don’t compromise warmth.

Eco-conscious comfort fabrics 

The outdoor industry is shifting away from ‘forever chemicals’, and the recycled 20D nylon shell and inner are treated with PFAS-free water repellent (polyfluoroalkyl substances). These super-soft-to-the-touch fabrics emphasise comfort rather than the rip-proof durability required for bivouacs or abrasive environments.

Premium features 

There’s a cosy, cinchable hood, neck and zip baffles, anti-snag sliders and a pocket for earplugs or valuables. A compression stuff-sack ensures the bag won’t occupy much space in your pack, but sadly it’s not seam sealed. 

Wilderness verdict: The Boost 650 combines comfort-oriented features with high-end details, doing so without being excessively heavy. It’s not the cheapest in class but it gets thumbs up for versatility for summer and shoulder season tramping and travelling.

Trail Specs: Therm-A-Rest Boost 650 0°C

Price $699.99
Temp rating 0°C limit (5°C comfort)
Weight 950g (reg)
Fill-power 650 hydrophobic down
Fill weight 400g (reg)
Sizes Small, regular, long; plus regular or wide dimensions.
Fabric 20D 100% recycled nylon ripstop
Variants Also available in -6°C

Gear radar

Trampers are spoilt for footwear choice with the arrival of four brands (well, re-arrival in the case of Garmont) to New Zealand. We particularly like the look of these boots.

Aku Trekker Pro II GTX

$599.99 / 1320g (m), 1120g (w) 

Italian brand Aku is the biggest new kid on the block. We’ve reviewed a couple of Aku boots already and are looking forward to testing the Trekker Pro II GTX. This wider-fitting boot balances reassuringly solid construction with ready comfort. The 1.6mm suede and ventilating Air8000 textile uppers are hard wearing, and the burly Vibram Curcuma sole has plenty of bite for soggy ground. 

Garmont Vetta Tech GTX 

$499.99 / 1080g (m)

Also from Italy, the light and technical Vetta Tech has a 1.6mm suede and synthetic upper, with an extensive rand. Its Michelin Offroad sole uses a flexible high traction compound. Combining those aspects with a moderately stiff but sensitive fit, active heel lock and flexible cuff, this boot is ideal for approach and tramping in steep, rocky terrain and riverbeds.  

Kayland Rocket GTX

$649.99 / 1400g (m), 1260g (w)

Kayland’s (Italy again) Rocket GTX is in the new class of boots that is moderately rigid but very light and semi-automatic crampon compatible. The seamless textile and TPU upper has a partial rand and there’s a tall cuff for support on a range of terrain. We noted the high volume midfoot and toe box. The boot is reported to be highly breathable, and well suited to the full range of transalpine conditions.  

Lippi Bravo Evo

$439 

Chilean brand Lippi originated in the Andes mountains. The top-of-the-range Bravo Evo mid-height trekking boot caught our attention with its narrow, technically-oriented Vibram XS Trek sole and reinforced nubuck leather upper with toe box rand. We haven’t tried it yet, but this B-Dry waterproofed boot looks to be well designed and durable.