Senchi Merlin Hoodie Ultralight Fleece Review

Fleece layers fall into that strange purgatory between utility and luxury. In all but the coldest conditions, it can be hard to justify the additional weight and bulk in your pack. However, they are great as beater layers to abuse instead of that delicate puffy jacket. You can hike, sweat, and spill food in them without risking their performance. They get wet, poked, and scratched, yet they just keep going. In the Senchi Merlin, you get all of this, just without the weight and bulk.

Stripped down and full of fishnet-like holes, the Merlin is as close to nothing as a fleece can get, almost. It promises supreme versatility and function, while also being hip in that hard-to-get kind of way. Even if you’ve heard of the Senchi, then you probably haven’t seen any of their stuff before. That’s where I was, so I jumped on the opportunity to test out this fleece when it fluttered my way. Could this thing change my view of the humble fleece? That’s what I hoped to find out.

READ NEXT — The Best Fleece Midlayers for Thru-Hiking

Senchi Merlin Alpha 120 Hoodie At-a-Glance

The Senchi Merlin is a really lightweight and super yellow fleece. I think that it really completes my stylish ensemble. Photo credit: seigenbrot

MSRP: $115
Weight: 6.6 ounces (size small)
Type: Lightweight, breathable fleece
Material: Polartec Alpha Direct 120 insulation (63% recycled polyester, Bluesign certified)
Features: 1/2 zip, hood, kangaroo pocket
Sizes: Unisex fit, XS-3XL
Country of origin: Made in the USA

Intended Use

The Senchi Merlin represents a lightweight avenue to boosting warmth in cold conditions where a puffy might be too hot and a shirt just ain’t cutting it. The premier breathability of the Polartec Alpha Direct fabric helps this fleece stay relevant across a wide range of activity levels, from layering in camp to steaming up a chilly climb. While you might get away with carrying this as your only warm layer in certain conditions, the Merlin is best suited as a cold-weather supplement to an existing three-season layering system. Combine it with a wind or rain shell, and you’ll be making toast in no time.

Circumstances of Review

I wore the Merlin from setting up camp at the end of the day until I started sweating the next day. It was a good lounger and a good hiker. Photo credit: seigenbrot

It’s been a hot summer, but I was stoked to bring my Bigbird yellow Merlin with me on a 6-day traverse of the CDT’s Collegiate West in the Colorado Rockies. We spent plenty of time above 12,000ft, which was ideal for finding cooler air and testing the capabilities of this fleece. I’ve worn it in a wide range of conditions, keeping it on beyond when I would typically strip in order to test the moisture management and breathability.

I also used it in lieu of my puffy as much as possible to push its lower temperature limits. I slept in it, ate in it, and hiked in it. It might not be a full thru-hike of testing, but my fleece sure is stinky. That’s gotta count for something.

Senchi Merlin Hoodie Features

The 1/2 zip and kangaroo pocket are in full view. Both are nice features of the Merlin. Photo credit: seigenbrot

Alpha Direct 120: The big story with the Merlin is the Polartec fabric. The Alpha Direct 120 is incredibly lightweight and upon close inspection, it’s easy to see why. It looks fluffy from a distance, but move closer and it’s hard to understand what’s going on. This fabric is fluffy, but it is also incredibly porous. You can see through it pretty easily. Really easy, actually. Weird.

Zip: The 1/2 zip on the Merlin is great for dumping excess heat. It’s hard to imagine Alpha Direct holding too much warmth with all those holes in it, but the Merlin is toasty. The zipper helps extend the comfortable exertion/temperature range of this thing, which is pretty sweet for a lazy layerer like me.

Kangaroo pocket: I prefer full-length zippers for maximum venting and versatility (and I’m pretty good at getting tangled up in my pull-over layers too), but at least the Merlin trades this for an awesome kangaroo pocket. Fair trade. It’s not super secure, but it’s a great spot for a phone, water filter, or hanging your digits around camp. It’s also perfectly located to remain useful when wearing a hip belt. Yep, that’s dope.

Senchi bag: Senchi includes a zippered mesh bag with all Alpha fleece purchases. This is intended to reduce microplastic pollution and protect the garment during wash cycles. That’s cool, smart, and responsible. And at less than an ounce, it can serve double duty as your trail ditty.

Trim fit: The unisex sizing corresponds roughly to standard men’s sizes. That said, the Merlin definitely falls on the “trim” side of the fit spectrum. I wear a men’s small in everything quite comfortably, and this fleece is right at my smaller limit. This makes it a good active layer, but I have zero space underneath for anything besides my baselayer/shirt. Definitely size up if you’re in between sizes or want room for layering underneath.

READ NEXT — A Light History of Alpha Direct, That See-Through Ultralight Fleece!

How’d it do?

I kind of really like this fleece. And at such a low weight, it’s easy to justify keeping it around. While I haven’t had the confidence to leave my puffy at home, the Merlin paired with a wind jacket might keep me just as warm, with the added benefit of boosted versatility. The fleece is a good, breathable active layer on its own, and is a little furnace as long as a breeze isn’t flowing through the gaps in the Alpha fabric. This means that I can wear it while hiking as well as in camp, whereas my puffy is pretty much just a stationary layer.

Size and fit

As I mentioned above, the Merlin in my typical size fits like a fluffy hug. That’s nice while I’m moving, and the next-to-skin feel is excellent, but if you have any intention of layering underneath, then it’s worth considering the next size up. Taking off my fleece without turning it inside out is a skill that I’ve learned, but it didn’t come easily.

It can also be a bit touchy to put on for the same reasons, but this is with me being extra careful not to stress the armpit seams. The fabric has proven durable so far, but its gossamer weight and holey appearance keep me cautious.

Versatility and Durability

Alpha Direct doesn’t look like your typical fleece. It’s fluffy and has holes in it. Breathable and warm? You betchya.

Durability has been good so far. However, I don’t expect any miracles. With care, the Merlin could last a very long time, but anyone interested in this piece should be realistic. This is a finely tuned, ultralight layer designed for extreme ounce-cutters. With few exceptions, reducing weight also reduces durability. I hate to speculate, but I wouldn’t put any money on my Merlin lasting as long as a typical fleece. Still, I’m going to love the ride.

It might be hard to believe it by looking at the Merlin, but with the Alpha Direct 120, it’s actually the most heavy-duty and durable offering from Senchi. Their other fleeces utilize the Alpha 90 and Alpha 60, which are lighter and more breathable. 

Originally intended to be used in conjunction with a shell material to provide warmth in insulated jackets, Senchi decided to let Alpha stand alone. If you want breathability, keep it this way. If you want more warmth, then add a shell, no sewing required. By deconstructing the synthetic puffy, we get the best of both the breathable insulation and protective shell with the ability to mix and match as conditions change.


Alpha Polartec is weird. Just how this stuff is manufactured is well beyond my comprehension, and it combines webbed threads for structure with tufty fluff for warmth-trapping insulation. Senchi takes this odd material and crafts it into a mid-layer that is both warm and extremely breathable. Don’t expect this thing to cut the wind or block a breeze, but in still conditions, it is surprisingly warm for being the garment equivalent of Swiss cheese. Toss on a wind jacket in blustery conditions, and you’re messing with some serious warmth.

During my trip, I only once needed to throw on my puffy over the Merlin when the katabatic winds picked up. With temps in the 40’s, conditions were mild, and the Merlin was almost all that I needed.


The fabric is breathable enough that I didn’t really miss a full-length zipper. The 1/2 zip was enough, and the kangaroo pocket was totally worth having on chilly mornings. On my morning bike rides or on breezy passes, I can feel the air on my skin. I run pretty hot, so this is a nice feature when I’m pushing the upper limit of temperatures where it is appropriate to be wearing a fleece.

Obviously, no fabric will breathe when it’s smooshed between back and backpack, so the Merlin still gets sweaty with a pack on, but it dries fast when allowed.

Senchi Merlin Hoodie Pros

The Senchi Merlin works great as promised and is pretty darn comfortable. I loved wearing this thing. Photo credit: seigenbrot

Lightweight: The scale doesn’t lie and the Merlin is one of the lightest fleeces out there. Factor in the 1/2 zip and kangaroo pocket, and you get an extremely functional layer for the weight of a few Clif bars. With no face or backing fabrics, the Merlin is pretty much just insulation. Nothing that you don’t want.

Versatility: Breathable by itself, and super warm under a shell layer, this dynamic duo should be able to handle most 3-season conditions in a way that a traditional puffy can’t.

Comfort: The Alpha Direct fabric has a pleasing softness that feels good even next to the skin. It’s also so lightweight that the Senchi Merlin is as unobtrusive as a t-shirt. There’s no bulk to get in the way.

Pocket, zip, and hood: While combined they probably double the total weight, I appreciate the added features of this fleece. A hood is a must for me, and the 1/2 zip and pocket are worth their weight, in my opinion.

Senchi Merlin Hoodie Cons

Bigbird yellow isn’t for everyone and with the limited availability of Senchi products, you might need to push your comfort zone and try something new.

Availability: You can’t love what you can’t get, and Senchi products can sell out fast. That’s the name of the game with popular items from small manufacturers, so don’t hate. It is what it is. And as of writing, there are Merlins available, though size/color choices are minimal.

Durability: Again, I hate to speculate and my Merlin is in fine shape, but if you’re super hard on your gear, then maybe Alpha Direct isn’t the fabric for you. It’s durable for what it is, but it exists near the absolute limit of lightweight. Baby accordingly.

Final Thoughts

It’s going to be hard to leave the Merlin off my packing list. It is just so good at so many things, and weighs so little. Photo credit: seigenbrot

I’ve never been much of a fleece guy, but the Senchi Merlin gives me few excuses to leave it behind. If anything, it will challenge my steadfast commitment to bringing my puffy along no matter the conditions. Usually, fleece layers are heavier and bulkier than my puffy despite not being as warm or protective from wind so it has been easy for me to pretty much ignore the category.

Now, however, by replacing my trusty puffy with the Merlin, I have a warm layer that is breathable enough to actually hike in. And when I’m hanging around camp, all I need to do is throw on a wind or rain shell, which I carry anyway, to essentially mimic the capabilities and use-case of that old jacket. This is a cool thought, though I’m not sure that I have the guts to try it.

So what am I trying to say? The Merlin is a sweet piece of gear that has the rare potential to change how I pack for backpacking trips in a profound way. Destabilizing as it is, that’s what good gear is all about. If you’re looking for an extremely lightweight fleece, then look no further than the Senchi Merlin.

Shop the Senchi Merlin Hoodie

Similar Lightweight Midlayers

Mellanzana Micro Grid Hoodie
MSRP: $86
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Material: Polartec Micro Grid

Read our review of the Melly here.

FarPointe Super Cruiser
MSRP: $90
Weight: 6.2 ounces (M’s M)
Material: Polartec Alpha Direct 120 or 190

FarPointe Alpha Cruiser
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Mountain Hardwear AirMesh Hoody (women’s)
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Arc’teryx Delta Hybrid Hoodie (women’s)
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The Senchi Merlin was donated for the purpose of review.

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Comments 5

  • Jingle bells : Sep 25th

    Fascinating material. Ordered a 120 Merlin after seeing this. Will use for camp/sleeping as I’ve never been thrilled with my quilt. The material is far, far too warm to wear in my 70-74 degree house. It has that same ultralight how is this possible factor like the first time you grab a rolled up DCF tent.

  • Jason Pauli : Nov 15th

    I just ordered the Big Bird in XL 2 days ago.
    I’m looking to get out a little more this winter and be lighter.
    It ended up being in stock with Senchi but I saw that Garage Grown Gear stocks them.
    Thanks for the review. I was glad to read another great one after ordering it!


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