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Arc'teryx - Sigma FL Pant - Men's

Arc'teryx Sigma FL Pant - Men's

$189.00$189.00
Changing the size selection, or changing the selected color after selecting a size, may change the associated price

Item #ARC00UB

Color:
Size:

Quantity:

+

Tech Specs

Material:
Fortius 1.5 (88% nylon, 12% elastane), DWR treatment
Seams:
not taped
Fit:
trim
Inseam:
[medium] 32in
Pockets:
2 hand, 1 hip
Waist:
adjustable, integrated belt
Claimed Weight:
13.1oz
Manufacturer Warranty:
limited

Why We Like The Sigma FL Pant

The Arc'teryx Sigma FL Pant is a lightweight option that we love to bring along for summer mountaineering and alpine climbing. Its Fortius 1.5 fabric is the lightest softshell from Arc'teryx, and it boasts four-way stretch, exceptional breathability, and reliable water-resistance for ideal protection in the alpine during warmer seasons.

  • Lightweight, breathable softshell pant for alpine adventures
  • Fortius 1.0 fabric is stretchy, breathable, and water-resistant
  • Double reinforcements ensure long-lasting durability
  • Trim fit includes articulated design for freedom of movement
  • Low-profile webbing belt stays secure under harnesses

Great pants for cold weather activities

  • Familiarity: I've used it several times
  • Fit: True to size
  • Size Bought: Large

I have bought these pants to replace my old Gamma LT for ice climbing and winter hiking. So far it's been great. Climbed and hiked in 32F - 42F and in ~ 15F with an extra base layer. Would be too warm for me above 50F, so really a cold weather option. The fit is good and they stretch a bit, which makes them great for climbing. The only downside is the price. If they turn out sturdy enough for 5-6 seasons similar to my previous gamma lt pants, I'd be happy with the purchase.

Great climbing pant!

  • Familiarity: I've used it several times
  • Fit: True to size
  • Size Bought: S/Reg

Typically I wear size 32 pants but have a bit of room in them so I went with a small on these. They are a bit on the tighter side but are by no means squeezing me to death or over accentuating anything that doesn't need to be, overall I will just use it as a reminder to drink less beer. These pants are also made to sit closer to your belly button/natural waist than not. Durability is still in question as they are still new to me, I have a reputation to destroy pants so I will see how that hold up. I am definitely being careful but they have shown no signs of wear from brief encounters of rubbing up against gym walls and rock.

The mobility in these pants are great! It is almost like climbing in no pants at all in the best of ways. The cinches at the bottom of the legs are a nice touch too, and the pockets don't interfere with a harness.

Nice alpine climbing pants

  • Familiarity: I returned this product before using it
  • Fit: Runs large
  • Size Bought: XL short

First of all I greatly appreciate that Arcteryx makes some of their technical pants with different inseam options. Most of these types of pants have zippers or other features that make a normal hem job at the tailor out of the question. These pants are a great product, my only reason for dinging a star is the huge difference between L and XL. For those of us that constantly straddle this zone, these two options were quite different. I looked like Freddie Mercury in the Large, and felt a bit like MC hammer in the XL. Well not quite, but you get the picture. Same goes for the Beta AR goretex pants. Hammer time XL in both is where I ended up.

Lastly, I always feel confident using BC for such acquisitions because they are fast and make returns super easy. So they get 5 stars.

Life Changing Pants

  • Familiarity: I've put it through the wringer
  • Fit: True to size
  • Size Bought: S/Tall

If you're tall and slim these pants are total game changer. Most American outdoor pants don't fit me particularly well, being too short or very baggy. These are very slim and non-bulky. The DWR coating is very good, it only seeped a bit after climbing a super wet and steep ice flow where the water was basically pooling in my lap.

Slim and agile

  • Familiarity: I've put it through the wringer
  • Fit: True to size
  • Size Bought: M/Reg

For quick reference: I'm a size 32" waist. The Sigma FL definitely fits into the fast and light descriptor Arc'teryx designates to these pants. For those who don't know, Arc'teryx designates their clothes into several categories based on the type of materials used... SL (superlight), FL (fast and light), LT (lightweight), AR (all-round), MX (mixed weather), and SV (severe). These FLs land between the SLs and ARs. Basically, they're a good mix between a super lightweight fabric and a medium-weight fabric. I feel most comfortable wearing these in weather between mid-50ºF weather to mid-70ºF weather. For anything cooler than that I'll switch to the ARs and for anything warmer I'm wearing shorts like the Arc'teryx Aptins or Gamma LTs. That out of the way, they fit on the slimmer side which I like. They have some stretch to them too which I value tremendously. I feel like these are very agile pants that are great for climbing or any situation where you might otherwise feel like you would blow out some stitching. I do have some large quads which are a little snug in these but not in a bad way—if you're a cyclist you may experience a similar fit.

Favorite Hiking Pants

  • Familiarity: I've used it several times
  • Fit: True to size

These have been the best pants that I have worn hiking and climbing yet, they are super stretchy, comfortable and fit really well.

Highly recommend.

Purchase Other Colors Besides Black

  • Familiarity: I gave it as a gift but have feedback to share
  • Fit: Runs small

I got these in black for my dad, which is somewhat a bad idea. They pick up quite a bit of lint and dust and black is not the best color to hide that. Additionally, the pants are a lot more slim fitting than the other Arc'treyx pants he own. He didn't size up so they are a bit tight. However, these pants are pretty comfortable for my dad and he wears them quite frequently.

Great pants - wrong size

  • Fit: Runs large
  • Size Bought: Large

Great product, impossible to tell what size you need without trying them on. I am 6' tall and 180lbs and slim (12% body fat) and the large was too big in both the waist and length.

Nice climbing pants

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: Small

I have ordered S/reg in stellar color. Pants look really nice but color is not as bright as on the website.
I'm 5'11", 150lb and 29-30 inch waist. The fit is perfect, slim but not tight. I can comfortable sit and move around.

Great for summer climbing

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: M

I initially bought a size L based on other reviews but it was a little big, so I returned it for an M size, which was definitely snug but not excessively so and I really like the slim profile. I have just got back from a 6-day summer alpine trip, worn virtually continuously and the pants worked out really well. Shed wind and dried fast, stretchy but kept its shape, useful zip pockets for bars or lip balm etc. Sitting in the snow for short periods was fine. Fitted over high ankle mountaineering boots very well. Looks fine in the bar and cafe. Definitely recommended.

Slim fitting, comfortable, good quality

  • Familiarity: I've used it several times
  • Fit: Runs small
  • Size Bought: Large

The sigma has a slim fitting, tailored look with tapered bottoms. The material is high quality with a clean finish and looks good. The fit is comfortable due to the stretch with no baggy areas.
They're an all around good pant for running errands or hiking trails. They are not the cheapest but the quality is definitely there.

Awesome climbing pants

  • Familiarity: I've used it several times
  • Fit: Runs small
  • Size Bought: Medium Tall

I'll echo what Stan stated in his review about the sizing. A bit trim for an Arc'teryx medium. I found the Medium still fit me like the Gamma LT and Gamma rock but snugger on the waist,
These pants are perfect for cool weather climbing and being in the mountains. Durable on the knees and seat like the Gamma rock but with a bit thicker fabric elsewhere for cooler weather.
I love that they added a thigh pocket!
Can't speak to the long term use yet but they're been awesome for climbing and some cold weather backpacking.
If you're in the lower end of the size chart, size up. I went with the Tall for extra ankle coverage, I could easily have got the Large and and some room to tighten the belt.

A Note on Sizing

  • Familiarity: I've used it several times
  • Fit: Runs small

I struggled getting the fit dialed in with these pants so I thought I'd post here to help others. About me: I'm 6'1", weigh 170-175, 33-34 inch waist and 33-34 inch inseam. Pretty typical climber build: tall and lanky. If you're anything like me, forget about the medium, even though it says 33 inch waist. The Arcteryx rep at the Denver store told me that the medium is actually sized from 31-33. For me, I could barely put them on. I got a large, tall and they fit perfectly.

I’ve used these a number of times climbing ice in CO this season, from warm days on dripping wet pillars to freezing and windy days on bulletproof ice, and these pants kept me dry and kept the wind at bay. Highly recommended!

Hey Stan,

Did the pants fit over your ice climbing boots?

Thanks!

To Kirk Anderson,
Sorry for the delay. Yes, the pants fit great over ice boots. They also have an internal drawstring at the cuff that allows you to cinch them pretty tight over the tops of the boots.

Super Comfy

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: Runs small

Love the cinch for the leg opening. Not a hassle to use at all, unlike other pairs I've used in the past. The fit seems to be somewhat small in the waist, but that's about it. Everything else feels great.

Arc'teryx

Men's Apparel
Alpha Sizes
 XSSMLXLXXL
Chest

36in

(94cm)

38in

(97cm)

40in

(102cm)

43in

(109cm)

46.5in

(118cm)

50in

(128cm)

Waist

29in

(74cm)

31in

(79cm)

33in

(84cm)

36in

(92cm)

39.5in

(100cm)

43.5in

(110cm)

Hip

36in

(92cm)

38in

(97cm)

40in

(102cm)

43in

(110cm)

46.5in

(118cm)

50in

(128cm)

Sleeve

32in

(81cm)

33in

(84cm)

34in

(86cm)

35in

(89cm)

36in

(91cm)

37in

(94cm)

Crotch to Floor:
Short

30.5in

(77cm)

31in

(79cm)

31.5in

(81cm)

32.5in

(82cm)

Crotch to Floor:
Regular

32.5in

(82cm)

33in

(84cm)

33.5in

(86cm)

34.5in

(87cm)

Crotch to Floor:
Tall

35in

(90cm)

36in

(92cm)

36.5in

(93cm)

37in

(95cm)

Numeric Sizes
 282930313233343638
Waist

28in

(71cm)

29in

(74cm)

30in

(76cm)

31in

(79cm)

32in

(81cm)

33in

(84cm)

34in

(86cm)

36in

(91cm)

38in

(96cm)

Hip

35in

(89cm)

36in

(92cm)

37in

(94cm)

38in

(97cm)

39in

(99cm)

40in

(102cm)

41in

(104cm)

43in

(109cm)

45in

(114cm)

Pant Inseam

32in

(81cm)

33in

(84cm)

33.5in

(85cm)

34in

(86cm)

35in

(89cm)

Crotch to Floor:
Short

30in

(77cm)

30.5in

(78cm)

31in

(79cm)

31.5in

(80cm)

32in

(82cm)

33in

(84cm)

Crotch to Floor:
Regular

32in

(82cm)

32.5in

(83cm)

33in

(84cm)

33.5in

(85cm)

34in

(87cm)

35in

(89cm)

Crotch to Floor:
Tall

35in

(89cm)

35.5in

(90cm)

36in

(92cm)

36.5in

(93cm)

37in

(94cm)

38in

(97cm)

How to Measure:
For best results, take measurements over your underwear.
Chest:
With arms relaxed at your sides, measure under your arms, around the fullest part of your bust/chest.
Waist:
Measure around your waist at the narrowest part.
Hip:
Standing with feet hip width apart, measure around your hips at the widest part.
Inseam:
From standing position, measure from your crotch to your ankle.
Sleeve:
With arm relaxed at your side and slightly bent, measure from center back neck, across shoulder to elbow and down to wrist.
Crotch to Floor:
With bare feet, measure from your crotch down the inside leg to the floor.
*Actual inseam length will vary depending on what Arc'teryx deemed suitable for end use footwear.