Monday, 14 February 2011

First Look: Forty Below Light Energy Shortie overboots

While looking at ways to ensure I keep my feet warm during ski tours in the winter I looked at several options. Switching to plastic double boots (T2's, Excursions, etc) and 3-pin bindings would be an expensive option and the boots would be an over-kill for my touring skis. Another option I had heard discussed was buying a HUGELY oversized pair of NNN-BC boots and using a felt liner but that too seemed like a 'hammer to crack a walnut' solution. I started to research overboots but all I could find were thin, ski-racing options until I remembered reading about Andy Skurka using early versions of the Light Energy TR Overboot from Forty Below to keep his feet warm in the frigid conditions he faced on some of his earlier adventures including his Sea-to-Sea and Nation's Ice Box excursions. The original LE overboot has a long, stretchy gaiter built in.

On Andy's more recent Alaska-Yukon epic I noticed on his gear list that he was using a newer model Light Energy Shortie overboot. Intrigued I contacted Joel Attaway at 40 Below. Joel confirmed that they were indeed now offering a lower fitting LE overboot with a stretchy knitted cuff. This sounded like the overboot would work better for me under my Patagonia Backcountry Guide ski pants with their built-in mini-gaiters. Joel was a joy to work with, his family has been skiing and mountaineering for decades, and he answered all my questions promptly and in detail. After giving Joel the dimensions of my ski boots I sat back and waited for my overboots to arrive.

Construction & materials:

The main body of the overboot is constructed from a nylon-faced neoprene material. The nylon-facing offers abrasion resistance while the 3mm neoprene insulates your foot from the cold. There is a very thin but tough, textured sole that is great for gripping snowshoe decks and ski bindings. The Shortie collar is a soft, stretchy, knitted affair that is really comfortable and conforms well to the cuff of your chosen footwear. Super chunky YKK zippers may seem like overkill to the UL'ers amongst you but you'll be thankful of them when trying to pull the overboots on whilst wearing mittens! Behind the zip is wide, comfortable neoprene flap that prevents snagging and cushions against the zip.

The overboots were perfectly sized to fit over my Crispi NNN-BC ski boots. I also tried them over my Montrail mids and Inov-8 330 trail runners that I would use whilst using snowshoes and they fitted well. The fit can be further customised using various insoles or even the Forty Below Simple Slipper. My size Large overboots weigh in at 346g for the pair.

Light Energy TR Overboots and ski bindings:

During discussions with Joel I enquired about using the overboots with Nordic ski bindings. The problem with Nordic boots and bindings is that they require holes to be cut in the sole of the overboot for the binding and boot to connect. Joel assured me that the tough fabric used on the sole would allow them to be customised depending on which binding system you use (NNN, NNN-BC, SNS, SNS-BC, etc, etc). The key is to use very sharp scissors and follow the 'measure twice, cut once' philosophy! I started by cutting a small rectangle so that just the binding bar was exposed but found that the binding engaged far easier by opening the aperture to allow more of the binding plate to engage with the grooves on the sole unit. For those rocking AT/ski-mountaineering set-ups then Forty Below also offer the Fresh Tracks model that will work better with Dynafit type bindings.

The hole in the sole doesn't mean that the boots can no longer be used in snowshoes or as camp wear. Slipping the supplied CCF foam insoles into the overboot seals up the hole to a suitable degree. There will be some snow ingress but it's minimal and doesn't appear to affect the overboot's ability to keep your feet warm.

So far I've been unable to test the Light Energy Shortie overboot in truly frigid conditions but I can confirm that they have kept my feet warm on wind-scoured mountain plateaus at -10C. I'm hoping they keep my tootsies warm on an up-coming trip to the far north. For next year Fort Below are working on a specific Nordic ski touring version of the Light Energy overboot that should come with the binding aperture pre-cut.


creep said...

good article.
I also was examining this item.
It serves as a reference.

I have been using neoprene bootie of crescentmoon for several years.
As for the thickness of neoprene, there is about 2.3inc, and the environment of -20℃ gains enough heat insulation power.

I want to try this item by all means.

Fraser said...

They look a bit clunky, but if it does the job...

The stitching at the forefoot looks like it's under a bit of stress in the pics. Any signs of weakness in that area?

This is all moot from my POV, as I've elected to hold off on any XC ski purchase until next year. :/

Joe Newton said...

Creep - send Joel an e-mail with any questions, he's very helpful.

Fraser - yes, they're a bit clunky looking but the only way you know you're wearing them is the snug warm feeling in your toes. The stitching isn't under stress in the forefoot, I think it's just the difficulty of stitching the thick upper around the shape of the forefoot area that makes the stitching look like that. They've not taken a bashing yet but I'll let you know how they fare when they do.

Fingers crossed that next winter, when you have your skis, Forty Below will have a specific Nordic overboot waiting for you.

Fraser said...

Yeah, sadly I only had one chance to try my snowshoes so far this winter. I WANT MORE SNOW!

Roman Dial said...


How well do they keep snow out? Snow coming through the hole on the bottom? Have you used them off-track, breaking trail?

Joe Newton said...

Roman - this was just a 'First Look' at the overboots, I haven't used them on anything more than a couple of day trips so far. At the weekend we were mostly on prepared trails, only breaking trail for short periods. When I was breaking trail it was on wind blown crust that broke in chunks and was easy to keep out. In deep powder it might be a whole different ball game. We'll see.

This weekend they will get a far better test when I take them out for a backpacking trip.

Unknown said...

Any company that makes specialist outdoor gear and home brewing equipment has my vote!

Even if there is some ingress, with your Crispis underneath it's not going to be a problem right?

Anonymous said...

How much warmth these would add? If I manage with my boots only down to a bit under -20C, could I manage -40C with these covers?

Just as an option to the neoprene overboots there is a looser fitting pile+shell options used at least by Finnish polar expeditions. I am making a pair for NNN BC boots myself (250g/m2 pile + GTX Proshell). It is not a too hard project, but at least little Finnish companies Urheiluareena and T-tossu make spesific models for NNN/SNS BC boots as well as for 75mm boots if you would like to buy one. (Also supports cottage businesses.) The pile versions are really warm, should work easily down to -40C but there are also version with thinner inners.

Some information about Urheiluareena's version:

Roman Dial said...

OK Joe, looking forward to the performance test!

Joe Newton said...

Dave - yes, they have their priorities right at Forty Below!

I'm not sure Roman was alluding to there being a problem with the possible snow ingress from a moisture point of view (you're right, the boots will cope with that fine) but more the accumulation of snow causing discomfort under the foot against the binding plate.

Korpijaakko - I haven't been in a position to put any kind of temperature rating to these overboots yet. I get cold in my current boots at around -20C or -15C if I'm moving slowly and sporadically when guiding with school parties.

Thanks for the link to the Urheiluareena overboots. Interesting to see different approaches. It would be interesting to put one of each overboot on different feet during the same trip.

Mac E said...

They look pretty similar to neoprene overshoes worn by cyclists (I've worn them myself)

The cycle shoe specific ones usually have a cut out at the heel and forefoot, the heel to prevent wear/provide grip and the forefoot for a Look/Time/SPD cleat. You can get mtb versions but they're much more cut away on the sole. I always used OZZO brand ones as they were pretty cheap.

Of course being neoprene they weren't waterproof but did provide some extra protection.

Philip Werner said...

Joel is a character. I was also thinking about using a pair of these for a long spring trip I'm taking where they is likely to still be snow around. Thanks for the photos. Very helpful.

Jörgen Johansson said...

The Hiihtokengän suojus look interesting, are they lined with pile? They seem not to be available in the shop, do they make them to order? My Finnish is pretty limited, so it is difficult for me to find out.

Anonymous said...


To my understanding the Urheiluareena's boot cover is line with pile. They have models for track/racing ski boots, NNN/SNS BC boots and 75mm tele boots. Only the track/racing boots model seems to be in the online shop. THe product line can be found from here: (model 798 is for BC boots, and for really cold environment you could buy model 830 and cut a whole for the binding)

Friend of mine told that the T-tossu versions (made in Rovaniemi) are of better quality. They have something like rough fleece as a lining, waterproof PU cordura outer and a bit stiffer sole with slight pattern. The heel is cut out and there is a hole to mount on a binding. You can also get T-tossu covers lined with pile for more warmth.

But those are also reasonable MYOG projects. I ques that at least T-tossu could make special models to order but Urheiluareena seems to have a standard product line. Maybe you could drop them a e-mail?

Jörgen Johansson said...

Thanks, I'll look into that. But I'll probably do a MYOG improvment on a boot cover I already have.