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Black Diamond Camalot X4 Review

These narrow headed cams fit in more places than Black Diamond C4s.
Black Diamond x4
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Price:  $80 List | $59.89 at REI
Compare prices at 4 resellers
Pros:  Flexible stem, narrow head, familiar size color scheme
Cons:  Relatively heavy, can kink when loaded in pods and pin scars
Manufacturer:   Black Diamond
By Matt Bento ⋅ Senior Review Editor  ⋅  Jan 30, 2018
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#7 of 8
  • Weight - 15% 7
  • Range - 15% 6
  • Horizontal Cracks - 10% 7
  • Tight Placements - 15% 7
  • Walking - 15% 7
  • Durability - 15% 7
  • Aid Climbing - 5% 8
  • Free Climbing - 10% 8

Our Verdict

Black Diamond X4s are an excellent complement to the Black Diamond C4s, offering more flexibility and narrower heads than their C4 counterparts, and keeping with the same familiar BD size range and color scheme. BD's unique take on the "alien" style cam includes their trademark double axle design in the larger sizes and a "stacked" double axle design in the smaller sizes to ensure the highest range possible from each cam. They fit well in flaring pods and pin scars, especially the offset sizes.

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Our Analysis and Test Results

Our testers were divided on these cams. Some liked them because they are stiffer than the Fixe Hardware Alien Revolutions making them easier to place, and others thought they were not flexible enough, causing them to permanently kink when loaded in odd positions. Our goldy locks testers agreed that the Totem Cams are just right, superior to both all the other small cams since they fit in more places than any other cam and can hold in offset and parallel placements.

These cams are the only double-axle "Alien" style cams.
These cams are the only double-axle "Alien" style cams.

Performance Comparison

The ergonomic thumb loop makes these cams great for free climbing.
The ergonomic thumb loop makes these cams great for free climbing.


A set of X4s from Yellow to Purple is heavier than the corresponding sizes of Metolius Ultralight Mastercams, and that includes an extra cam in the Metolius line to cover the same range. The same goes for the Fixe Hardware Alien Revolutions and they're even lighter than the Metolius. The Totem Cams in the same size are about 20g heavier than the X4s, but we consider the fact that each Totem cam functions as an offset to be a major bonus in the weight department.


X4s are available in six sizes covering cracks from 8.4mm to 41.2mm in width. That's sub-tips to thumbs stacks. Our testers are especially fond of the purple (fat fingers), and Green (thumbstacks) sizes because they fit in narrow pods and flexible stems, and have the same feel and familiar range as the corresponding C4 sizes we've been using for years. Experience with the Black Diamond ranges and sizing drew a few of our testers to the X4s, as they didn't need to learn the subtleties of a new brand with different ranges and colors.

The beaded sheath design protects the stem in a horizontal placement and avoids a few patent infringements.
The beaded sheath design protects the stem in a horizontal placement and avoids a few patent infringements.

Horizontal Cracks

These cams handle horizontal placements much better than stiffer models like Black Diamond C4s, Wild Country Friends, and DMM Dragon Cams. Their beaded sheath over a flexible cable allows the cam to bend in the direction of pull without permanently kinking like a more rigid stem would. More flexible cams like Totem Cams and Fixe Hardware Alien Revolutions handle horizontal loading better.

These cams aren't as narrow-headed as the Aliens.
These cams aren't as narrow-headed as the Aliens.

Tight Placements

Black Diamond X4s have narrow heads that fit and protect where C4s and Ultralight C4s can't go. Pin scars, flares, and narrow pods are what these cams were designed for. The offset sizes are particularly great in these situations. Totem Cams have them beat though, and are a few millimeters narrower.


These cams are relatively stable, but they don't have an extendable sling like the DMM Dragons or the Fixe Hardware Alien Revolutions, making them more prone to walking. Bring along some alpine draws and extend your placements when the pitch wanders, and walking won't be an issue.


As previously mentioned, these cams are more liable to kink than more flexible cams when placed in pins cars or any situation where the cam is loaded in a vertical orientation but no in the proper direction of the load. More often than, this only results in the cam looking a little bent, but not really affecting the functionality of the cam. We feel that the thumb loop on this cam is heavier and more durable than that of theMetolius Ultralight Mastercams and the Fixe Hardware Alien Revolutions. If you plan on doing loads of aid climbing, this burly thumb loop feels like it will withstand a lot of Fifi hooking and bounce testing. While heavy, the aluminum bead sheath and hard aluminum trigger make these cams durable.

Aid Climbing

Our Cams tend to get the most beat up during aid climbs, where every piece gets weighted, often in strange positions pushing the limits of their designs. The beefiness mentioned above makes them great for aid climbing, and the thumb loop lets you clip in higher than cams without a thumb loop, like the Metolius Ultralight Mastercams and the DMM Dragon Cams. The X4s still don't trump the Totem Cams when it comes to aiding, since Totems unique design allows them to load on only two lobes, and function as an offset cam.

Free Climbing

These cams are great for free climbing. Our testers are all very familiar with how each BD sizes corresponds to how their hands feel in the cracks, making it easy to select the right cam. The thumb loop makes these cams easier to place when you're pumped and give you something soft to gnaw on if you have to hold the cam in your mouth.

A .3 X4 sightly under-cammed in a tips crack.
A .3 X4 sightly under-cammed in a tips crack.

Best Applications

For those climbers who swear by Black Diamond's cams because of their range, availability, and familiarity, X4s are a great way to expand your rack in the finger sizes. The X4s will fit in pods and pin scars better than C4s and DMM Dragon Cams. For our favorite small finger sized cams, have a look at the Fixe Hardware Alien Revolutions.


These are $80 per unit, a full set of six for $480 — considerably more than the same six of the smallest Metolius Ultralight Mastercams. Because of their durability and range from the double axles, we feel they are a good value. But, if you can live without a thumb loop, the Mastercams are a great option and take home our Best Buy Award.


The Black Diamond X4s have the quality and durability we've come to expect from Black Diamond and complement a rack of C4s nicely. If you're looking for a cam that fits in a wider range of placements, check out our Editors' Choice award-winner, the Totem Cam.

Matt Bento