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Metolius Open Loop Sling Review

Our Top Pick for Building Anchors due to the ease of untying tight knots
Metolius Open Loop Sling
Photo: REI Co-op
Top Pick Award
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Price:  $13 List | $5.95 at Backcountry
Compare prices at 2 resellers
Pros:  Relatively easy to untie weighted knots, comes in large selection of widths and lengths, affordable
Cons:  Bulky for 11mm, not the best friction for alpine quickdraws, not as smooth as others
Manufacturer:   Metolious
By Andy Wellman ⋅ Senior Review Editor  ⋅  Apr 11, 2019
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73
OVERALL
SCORE


RANKED
#6 of 12
  • Handle - 25% 7
  • Knot Test - 25% 8
  • Alpine Quickdraw Test - 20% 7
  • Weight - 15% 8
  • Bulk - 15% 6

Our Verdict

The Metolius Open Loop Sling is our Top Pick for anchor building because it is easier than any other sling that we tested to untie knots after they have been weighted, a critical component to any anchor building sling, and one that will be greatly appreciated by anyone who has battled to loosen a welded knot while trying to quickly leave the belay. It also comes in the widest variety of both widths and lengths of any that we reviewed here up to 480cm (16' long!), allowing for the greatest amount of customization to your anchor building needs. We tested the 11mm wide, 120cm long version, which allowed us to easily equalize two anchor pieces with a figure-eight knot. While many other slings will also work for this purpose, we are convinced that the Open Loop Sling is the ideal choice.

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Overall Score Sort Icon
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Pros Relatively easy to untie weighted knots, comes in large selection of widths and lengths, affordableLow weight, very thin, handles great, affordableLight weight, low bulk, knots untie relatively easily, affordableMost affordable, handles great, elastic stretch properties when catching a fallHas same dynamic elongation as a climbing rope, minimizes fall forces, core protected from UV and abrasion by the sheath
Cons Bulky for 11mm, not the best friction for alpine quickdraws, not as smooth as othersWeighted knots harder to untie than thicker slingsNot as soft a handle as other top scorersHeavy, bulky, lots of friction in alpine quickdrawsHeavy, bulky, doesn’t carry well in an alpine quickdraw
Bottom Line Our Top Pick for Building Anchors due to the ease of untying tight knotsThe best climbing sling due to its great handle and low weight and widthA fantastic lightweight flat sling that is also affordableThe best option for traditional climbers who want to save some moneyA dynamic piece of climbing rope that is sewn into a sling and is ideal for reducing risk while clipping in direct to belay or rappel anchors
Rating Categories Metolius Open Loop... Mammut Contact Dyneema Black Diamond Dynex... Nylon Sewn Runner Beal Dynamic Sling
Handle (25%)
7.0
9.0
7.0
9.0
6.0
Knot Test (25%)
8.0
5.0
7.0
4.0
8.0
Alpine Quickdraw Test (20%)
7.0
10.0
8.0
5.0
4.0
Weight (15%)
8.0
10.0
9.0
4.0
1.0
Bulk (15%)
6.0
10.0
9.0
4.0
4.0
Specs Metolius Open Loop... Mammut Contact Dyneema Black Diamond Dynex... Nylon Sewn Runner Beal Dynamic Sling
Type of Fiber Dyneema/Nylon weave Dyneema Dynex Nylon Dynamic Rope
Measured weight 47g (22g for 60cm) 19g 20g 37g 78g
Width Tested 11mm 8mm 10mm 18mm 8.3mm
Length Tested 120cm 60cm 60cm 60cm 60cm
Strength 22Kn 22Kn 22Kn 22Kn 22kN
Widths Available 11mm; 13mm; 18mm 8mm 10mm 18mm 8.3mm
Lengths Available 25cm; 60cm; 120cm; 240cm; 480cm 60cm; 120cm 30cm; 60cm; 120cm; 240cm 30cm; 60cm; 120cm; 240cm 60cm; 120cm; 150cm

Our Analysis and Test Results

Compared to the competition, the Metolius Open Loop Sling is relatively average, which still means that it is a good sling, worth buying and owning. However, the only area that it shows exceptional performance is in our knot test, in which we compared how easy it is to untie figure-eight knots once they have been weighted and tightened. We don't want to suggest that it is simply as easy as can be to untie these knots in this sling, as anyone who has hung on a knotted sling at a hanging belay for an hour can attest, but we found it to be far easier than most of the competition. This seems to be due to the relative thickness of the flat sewn sling compared to its width. It also comes in a variety of widths — 11mm, 13mm, or 18mm — and the largest selection of different lengths to choose from. This allows one to purchase exactly the lengths you need in order to equalize anchors as you like. The 120cm length that we tested is perfect for double bolt belays with a figure-eight knot to serve as the master point, but a 240cm length would be ideal for equalizing three traditional pieces that may be located in two different crack systems.

Both of these slings, the Metolius Open Loop Sling on top and the...
Both of these slings, the Metolius Open Loop Sling on top and the BlueWater Titan Runner on the bottom, feature roughly equal amounts of Nylon (color) and Dyneema (white) fibers, although they use a different weave pattern to accomplish this.

We compared this sling extensively to the BlueWater Titan Runner, which is another sling that uses both Dyneema and Nylon in its construction. The Open Loop Sling, like many other Dyneema slings, is made primarily with Dyneema in the middle as the load bearing part of the sling, but with a larger than average amount of Nylon on the edges to provide elasticity and color. The Titan Runner, on the other hand, integrates the two types of fibers, interweaving them together. This way of weaving the fibers likely does a better job of combining the positive attributes of both fibers (strength and elasticity), but as a much thicker, wider, and heavier sling, that was harder to untie knots in, we think that the Titan Runner simply isn't as easy or enjoyable to use, and is therefore not as ideal a choice as the Open Loop Sling for anchor building.

Monster Sling
In previous reviews we referred to this sling as it used to be known, the Monster Sling. You may still encounter this name in other locations on the internet. This sling is made of Metolius's Monster Sling material, but is now called the Open Loop Sling, and remains relatively unchanged from previous versions.

Performance Comparison


The Metolius Open Loop Sling equalizing two bolts in this anchor in...
The Metolius Open Loop Sling equalizing two bolts in this anchor in Red Rocks. As the easiest sling to untie knots in once they have been weighted, we recommend this sling for Anchor Building.

Handle


The Metolius Open Loop Sling is made of a blend between Dyneema and Nylon fibers, with the white Dyneema fibers in the middle, and the green Nylon fibers woven around the edges. It is a flat sewn sling that nevertheless is a bit thicker, and slightly ovular in shape, compared to the Camp USA 11mm Express Dyneema Sling.


In the hand it is smooth and soft to the touch, but not as much as the strictly Nylon slings such as the Black Diamond Nylon Sewn Runner. The edges of this flat sling are ever so slightly abrasive, as we have found on many of the other flat sewn slings, although this complaint is very minor. The bar tacking, however, is larger profile and has two tabs of extra sling material hanging off each end, allowing for easier hang up on carabiners than the Mammut Contact Sling, which effectively negates this feature.

This photo shows the roughly 50/50 breakdown between the white...
This photo shows the roughly 50/50 breakdown between the white Dyneema fibers and the green Nylon ones. You can also see how this sling is relatively thin for its 11mm width, and has a roughly average sized bar tack.

Knot Test


This sling excelled in our knot test, the main reason why we recommend it as the best choice for equalizing anchors. At 11mm wide it is not as skinny or as wide as the slings that we found to weld the tightest when knots are weighted. It is rather square cut, which actually makes it ever so slightly harder to tie knots in without twists (we found that twists in the knots don't compromise their ability to stay tied), but which allows it to not tighten as much, and thus be far easier to untie.


The only other sling that scored equal to it in this test had virtually the same attributes — the Camp USA 11mm Express Dyneema Sling. Both of these are easy to untie, regardless of whether the knot is a figure-eight or a clove hitch.

Knots are easy to tie and untie with this sling, especially clove...
Knots are easy to tie and untie with this sling, especially clove hitches.

While this knot may not look the cleanest, we found that the very...
While this knot may not look the cleanest, we found that the very slippery nature of this sling, plus the fact that its 11mm wide, made for extremely easy untying of welded, weighted knots.

Alpine Quickdraw Test


The slings that performed the best at our Alpine Quickdraw Test were the ones that are thinner and less bulky than all of the others, so that the least amount of friction between different loops of the sling or the carabiner make it easier to equalize the sling to the proper length. Like the Camp USA Express Sling, which had very similar attributes, the Open Loop Sling scored in the middle of the field.


The large tabs on the bar tack also lowered the score a bit for this sling, because those tabs are more likely to hang up as they pass over and through a carabiner, regardless of whether tripling up the draw or extending it.

Despite the fact that we tested a 120cm version of this sling, one...
Despite the fact that we tested a 120cm version of this sling, one can still triple it up into an alpine quickdraw, it just hangs too low off the harness... This one performs about average in our testing.

Weight


For this review, we tested the 120cm (47") version of this sling, and found it to be 47g, only 2g heavier than advertised on Metolius' website. By comparison, the 48" version of the BlueWater Titan Runner weighed in at 65g, a considerable amount more.


For comparison to the other double-length slings in this review, however, we are forced to rely on what Metolius advertises as the weight of their double-length (60cm) sling, which is 22g. This is competitively light with the Sterling Dyneema Sling, although just a few grams heavier than the lightest slings in this review, such as the Petzl Pur'Anneau Sling.

The 120cm length sling we tested weighed 47g, far lighter than the...
The 120cm length sling we tested weighed 47g, far lighter than the similar length Titan sling. When considering the 60cm version, this sling is light, but not as light as the lightest in this review.

Bulk


The 11mm width of this sling makes it one of the wider Dyneema slings, as a large amount of these types are either 10mm or even skinnier. That said, it is still considerably thinner than either of the Nylon slings that we tested.


Compared to the other two slings that are also 11mm wide, it is basically the same shape as the Camp USA 11mm Express Dyneema Sling, but is a fair bit thicker than the Trango Low Bulk 11 Sling, which we awarded a higher score.

Showing the bulk of the three 11mm wide slings in the middle...
Showing the bulk of the three 11mm wide slings in the middle, compared to the widest and thinnest slings in the review. Blue and white Camp USA 11mm, green and white Metolius Open Loop, and orange and white Trango Low Bulk. On the top for comparison is the Sterling Nylon (17mm) and on the bottom is the Mammut Contact (8mm).

Best Applications


We feel that the best application for this sling is for equalizing pieces of protection at anchors. Its blend of Dyneema and Nylon fibers, combined with a shape that allows one to tie knots, weight them, and then still untie them with relative ease, makes this an ideal choice for that purpose. Purchased in a 24" length, it performs just fine for extending protection pieces on lead, although wouldn't be out top choice for that purpose.

Andy reaching the belay atop pitch 9 or 10 of Resolution Arete, Red...
Andy reaching the belay atop pitch 9 or 10 of Resolution Arete, Red Rocks, having cleaned many slings along the way and conveniently thrown them over his shoulders to be able to keep moving faster.

Value


For the 120cm version expect to pay around $13 retail, or around $8 retail for a 60cm sling. This is an excellent price for a Dyneema sling, ranking as the most affordable for this type of fiber in this review. Since we recommend it as one of our top picks, we think this presents awesome value.

Stefan using the Metolius Open Loop sling to equalize the double...
Stefan using the Metolius Open Loop sling to equalize the double bolt anchor at the start of the Naked Edge in Eldorado Canyon, CO.

Conclusion


The Metolius Open Loop Sling is our Top Pick for Anchor Building, and is also an economical choice for use as a traditional lead sling in the double-length as well. Its blend of fibers, many length and width choices, and ease of untying knots all set it apart from its competitors, and are all reasons why we choose to recommend it.

Andy Wellman