First impressions: Mountain Hardware Phantom 45

“in this labyrinth where night is life… the Phantom 45 is there, inside my bivvy bag”

I accepted a few years ago that what I experienced in my Snug-pak Jungle Bag was more akin to feral survival than sleep (it is retired to house duty), and although I have been very impressed with the general UK hills usefulness of my MH Lamina 20 it remains a tad pudgy for ultra-light, small pack use for missions like the GR20 or the MMM. On borrowing a friend’s Phantom 32 (also Mountain Hardware) for last year’s MMM, it was quickly on my radar of possible summer sleepers.

Now, choosing your arsenal of sleeping bags is a very tricky game, and doesn’t come cheap when you want to invest in the best. What balance of temperature ranges, weights, and materials will cover the majority of situations you will encounter? As one of the ‘big 3’ items in your gear it determines much of the weight you will carry, but at the end of the day is also most responsible for keeping you alive and refreshed. Just to note, I’m normally a warm sleeper: in the house I just lie under a sheet in the summer and use a 4.5tog quilt in the winter (+ a rug if it’s freezing out).

At 1400g, the synthetic Lamina 20 excels at allowing you to jump in soaking wet and is comfortable from +7 to -7, which frankly covers all 4 seasons in our high country and takes care of that dangerous ‘cold wet’ zone we frequently are served. I decided that replicating this with down would not be in my best interests in terms of flexibility: all I would achieve is saving 600g. I reckoned that a bag that could cope with close to 0 would give me 2.5/3 season use in the UK, be ideal for hiking trips on the continent where there may be much warmer nights, and weigh as little as possible to maximise space and gram savings. A full-length zip would also add to the comfort range.

Having enjoyed a PHD Hispar for a couple of expeditions, they were my first stop for a summer bag. Excellent quality gear, but it was going to be expensive to get the features I wanted as their ultra-light bags are incredibly minimal and I need something for more than races.

The Marmot Atom was also on my list. I saw one in Jackson Sports and it had a lovely loft and was very well constructed, with probably the best zipper set-up I’ve seen on a sleeping bag. Not a bad price either, but I found mixed reviews about it’s temperature performance (rated 5 degrees) and it was a smidge heavier due to slightly more durable fabric.

The Rab Neutrino 200 couldn’t be overlooked for value and awesome colour, but was slightly heavier too and only had a half-zip.

I did consider investing in a Z-packs hoodless sleeping bag which are insanely light and easily open into a quilt for warmer nights, but the unusual design would probably not pass muster for race events like the MMM. Might still revisit this idea if I do a through-hike like the CDT.

Finally, there was the Mountain Hardware Phantom. These bags are both very light and happen to rate a few degrees lower than they are designed for. Too good to be true? Well, a lot of the reviews seemed to indicate that they were indeed very warm. I was positively boiling last year in the 32, so my attention drifted upwards to the 45… supposedly much the same as the Marmot Atom, but actually rated to about 0 (32) for the lower comfort! A double ended full-zip, good foot box, and tight hood complete the package. At a mere 530g including stuff sac, for only £180 in the sale, there was simply no reason to choose any other bag.


The weight quoted above is what I weighed it at on the digital scales, and the stuff sac is about the size of a DVD: a reckon a green Exped drybag would be a good substitute for more protection. I’ve since had the bag out on 2 overnighters and a 4-day trip to the Cairngorms, each time bivvying inside a Rab Survival Zone. The bag lofts really well when you get in and I have not seen any feathers poking through yet, which I’m used to expecting from most light down gear. The zip snags much less than on the Lamina, and has a good baffle. Being super light for moderate temperatures, there are no neck/shoulder baffles. This is fine, as the bag cuts in close over the shoulders with a good mummy hood: fully zipped it seals nicely around your head to stop the body heat escaping. I am just about 6ft tall and the bag is at the limit height wise… anyone taller, I would recommend the long model.

The first 2 trips were up around 13-15 degrees in very breezy locations. No bother. The 4 day was based at Glenmore campsite and ran the gammut from sticky, still rain to windy, and heavy dew. The zips were most welcome on the hot nights, but everything gets very damp in the bivvy when it is less than wide open… not an option in the rain or with thousands of midges on the hunt. The bag stayed comfortable, and dried rather well airing my friend’s tent for the day. The last night had rather a cool breeze and clear sky. It must certainly have dropped to single figures as there was a heavy dew and yet more condensation inside the bivvy (bit more than I would expect for Pertex Shield). After 3 days of running and feeling a bit ill, it’s not much of a surprise that I got a bit cool, but closing the zipper and cinching the hood stopped my heat escaping. I was just wearing a threadbare LS merino 200 top.

So far, so good. Just a few days until the MMM, then I’ll no doubt be looking to test the bag into the lower temps of late autumn. I don’t think a cool, damp bivvy will work very well, but it should be ok on those crisp nights and I think in a tent, wearing decent long base layers and feeling fresh it could well cope with a touch of frost. It may even fit inside the Lamina to extend it’s range perhaps down to -12 or so… definitely covered for anything the UK can throw at me. The last foreseeable addition to the arsenal might be a PHD combi bag/combi hispar for cold lightweight trips. A wide cut bag that is good to -5 on it’s own or would take the Phantom as an inner for -15 or beyond. Both combined would be lighter than the Lamina. I’ll keep you posted.

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