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DMM Big Boa HMS I Beam Keylock Carabiner


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    Big Boa HMS I Beam Keylock Carabiner

    The DMM Big Boa HMS I Beam Keylock Carabiner is a big, bad belay biner for when you need a combination of low weight, high strength, and huge capacity. The I Beam construction gives the Big Boa one of the highest strength ratings out there, and its keylock nose eliminates rope snags.
    • Item #DMM0035

    Gate Type
    keylock nose
    Major Axis Strength
    25 kN
    Minor Axis Strength
    10 kN
    Open Gate Strength
    8 kN
    Gate Opening
    [Screwgate] 25 mm, [Quicklock, Locksafe] 24 mm
    Claimed Weight
    [Screwgate] 2.9 oz, [Quicklock, Locksafe] 3 oz
    Recommended Use
    Manufacturer Warranty
    1 year

    Tech Specs

    What do you think about this product?



    DMM Boa” from DMM Climbing

    The Boa is a high volume carabiner with a large gate opening and extended top bar, making it easy to clip with thick ropes and slings, and allowing it to accommodate multiple attachments. Its asymmetric shape sits naturally in the hand for easy handling, and I-Beam construction means that despite its large size, the Boa is still relatively light.

    >Rating: 5

    Great & Easy to Use Carabiner

    I've used it several times

    I've used the carabiner about 5 times now and I love it. The large size allows for easy clipping on to my harness and the look is very sleek. I recommend this product.

    >Rating: 4

    Good Quality

    Purchased the Locksafe and Quicklock. I wanted to get that security that it would close sufficiently and easier versus a screwgate. Though all of them do the job. The difference: The Locksafe has pull and twist mechanism whereas the Quicklock has the twisting component only. Love the quicklock. I feel safe and it is really easy to use. The locksafe is nice, but a bit tedious on top of routes if your hands get a bit tired. I would recommend either for sure but the quicklock is my go to.

    >Rating: 4

    Great at the Anchors

    I've used it several times

    I'm real happy with the Big Boa as the workhorse on an anchor's masterpoint, especially in aid/big wall scenarios. The size of this thing lets you clip many systems into the master without getting too cluttered. Everyone else is right though - its I-beam shape isn't the best for rappels - If you're looking for a big rap 'biner, go with a Rocklock or something else with a round profile.

    >Rating: 5

    Light. Roomy. Safe.

    I've put it through the wringer

    Like most things, there are specific tools for specific jobs--the DMM Big Boa is my go-to tool when I need a biner with a huge carrying capacity, easy gate, and relatively lower weight. Right now I have one of these on my rack, but I'm looking to pick up a couple more. This guy ends up serving as the powerpoint on most of my anchors, and while I have rappelled on it in a pinch (buddy's got my belay biner, etc), I don't typically rappel too often on it... any i-beam biner won't do as well as a solid-stock as far as durability is concerned, but like I said--different tools for different jobs. at $12.72 right now, it's a total steal.

    >Rating: 2

    No so great rappel binner

    I've put it through the wringer

    Personally I think the Quicklock DMM Big Boa is the best rappel binner on the market. It is very roomy and fits a lot of ropes. It is easy to open and close with both left or right hand. Locksafe is a little bit awkward and hard to operate with one hand. If you are ready to invest $20 in rappel/belay locker just get DMM Big Boa Quicklock. BTW, Black Diamond Rocklock is a close competitor with much better price tag. If you are on a budget or if you already have Rocklock you do not really need this binner. upd Jun 5th, 2013. After couple months of intensive usage my Boa got really grooved. Much worse then my BD Rocklock in several years. Thus I decrease rating from 4 stars to 2 stars. Probably 1 start would be more adequate for this metal quality.

    Try investing in a little rope wash next time, especially if you climb on sandstone.

    An inherent disadvantage to I-beam construction vs the Rocklock's solid bar. I don't know if its fair to blame the metal quality when there are so many other factors. Like Coldfinger above indicated, your rope's condition may have changed between when you used the Rocklock and switch to the DMM. But it is worth noting that skeletonized or I-beam biners will wear worse than solid bar construction. Something to consider when looking at lightweight biners.

    Thnx for the input Aaron. FYI, the only thing have changed after I switched to Boa is that I began to wash my ropes about two times more ofter - it was a natural reaction to increased binner wear. Unfortunately it did not help.

    >Rating: 5

    Nice and roomy

    If you want lots of room for anchor building, this makes a great biner, and the screwgate comes at a reasonable price that is competitive with the identically sized Petzl William. The DMM Locksafes tend to carry a huge price premium, and you might as well buy the Petzl William Tri-Act. This carabiner's basket size is almost identical to the Petzl William carabiner, and weights are similar. If you need to do some rigging with multiple hitches and ropes, this kind of carabiner is indispensable. If you climb in the winter, size does matter! The strengths listed by Backcountry do not agree with DMM's website. The numbers are 25kN, 8kN (open gate), and 10kN (minor-axis). This is a great carabiner. But so is the Petzl William. You can't go wrong with either.

    >Rating: 5

    Favorite carabiner!!

    I've been using this biner for belaying for the past couple seasons and I must say, this thing is DURABLE. I've had a fairly insignificant amount of wear from the rope, even with moderate-heavy use in the past 2 years. It's huge so the belay loop on my harness feels as if it's angel hair pasta when I'm all hooked up. I have the auto-locking (double action) version with the red gate, and I can open it really easily with just one hand. This is such an amazing belay biner and I will surely buy another one once mine is worn out.

    I forgot to mention that while belaying, I've never gotten this biner in a cross-loading situation. It ALWAYS has stayed in place without rotating!

    I believe the red gate is the quicklock version, which requires only a single action (twist) to unlock the gate. The green 'locksafe' version requires a pull and a twist to unlock.

    Oops, my mistake, you're correct Dan! Just the twist on my red gate - meant to write"single action" thanks for catching that ;)

    >Rating: 5


    I got this primarily for my top rope anchor. It's built more beefy than my BD rocklock and rated for 4 more kN. Also, I got this 'biner in the quicklock version which is great for teaching newbie friends how to belay. The spring loaded locking action takes that tiny bit of doubt out of my head. A small note is that this is difficult to open one handed, as the gate lock must first be pulled up before twisting, but as I got this to use for a top rope anchor and belaying, this is actually preferable to me.

    It sounds like you have the 'locksafe' version, not the quicklock. The red quicklock version requires only a single action (twist) to unlock the gate. The green 'locksafe' version requires a pull and a twist to unlock.

    >Rating: 5

    great opening

    As a carabiner on your harness this one is huge and has a great big opening. It makes it easy to use.