Metolius Offset TCU Cams

Metolius Offset TCUs, Blister Gear ReviewMetolius Offset TCU Cams


  • Offsets are composed of two small lobes and one larger lobe
  • 13 mm (0.51″) Monster Sling webbing (36% Dyneema/64% nylon)
  • Range Finder tells you at a glance if you’ve chosen the right size cam for the placement
  • Optimized cam angle for more outward force
  • Wider cam faces for more grip
  • U-shaped body for greater durability and unparalleled control during placement and retraction
  • Machined cam stops
  • Color-coded sewn slings and tubing
  • CNC machined for much greater precision than stamped or extruded cams
  • 7075-T6 aluminum
  • Sizes #00/0-#3/4
  • Hand built, inspected and individually proof tested in Bend, Oregon

Range: 8.3-118.1mm

Days Tested: 15

Test Locations: Castle Valley, Utah; Eldorado Canyon and South Platte, Colorado


Years ago when I first saw an offset cam (a CCH Alien, to be exact) hanging off someone’s harness, I remember being surprised by its existence, wondering how one might place such a device. Without ever using them, I quickly wrote them off as a niche piece of gear with an impractically narrow application.

For those who haven’t run across them yet, offset cams—also frequently referred to as “hybrids”—are cams with lobes of different sizes on the same device. It is perhaps easiest to picture offset cams as straddling between the normal sizes in a product line. Consequently, offsets with four lobes (such as the Alien, Basic, or Mastercam) have a pair of lobes in one size on one side of the head, and the lobes on the other side of the head in an adjacent size. TCUs, or Three Cam Units, have only three lobes, one in the larger size, and two in the smaller size.

Metolius Offset TCU, Blister Gear Review
TCUs with One Larger Lobe and Two Smaller

Having lobes of different sizes is the defining characteristic that makes the cams suited for flaring or uneven placements. In cracks that taper rapidly as they recede from the surface of the rock, regular cams might have the two deepest lobes appropriately retracted while the outer pair of lobes sits uselessly open, unable to reach the rock that has opened up away from them.

Even in less extreme examples, where all four lobes are at least making contact with the rock, having a dramatic difference in the extent to which the lobes are retracted is less than ideal at best, and extremely dangerous at worst.

Why Offsets?

Offset cams are designed to solve this problem. The smaller inner lobes fit the narrower part of the crack while the larger pair of lobes makes good contact in a wider part of the crack. As such, all the lobes are retracted to a similar extent. For this reason, they’re fantastic at protecting flares or pin scars (the only cams that will, in many cases), but not really suited for the parallel-sided cracks that your garden-variety cam is built for. As a result, offset cams are usually thought of as being made for aid climbers hoping to tackle tricky clean aid, without offering much to the free-climbing community.

In the years that followed my initial double take, I’ve moved to Colorado and spent much time climbing in Eldorado Canyon and the South Platte region, where flaring cracks or pods are quite common. This experience, combined with a handful of climbing trips to North Carolina (horizontal eyebrows, anyone?) re-opened for me the discussion about offset cams.

Metolius Offset TCU, Blister Gear Review
Dave Alie, Outer Space, Eldorado, Colorado.

I’m hardly the first climber to be driven to offsets by the nature of the rock at their home crag. The offset cam market, once ruled by the Colorado Custom Hardware Alien, has seen the arrival of offset versions of both the Metolius TCU and Metolius Mastercam, the Fixe Alien (a reincarnation of the CCH version), and the Totem Basic.

Having learned traditional climbing alongside older generations of the Metolius TCU, I was familiar and comfortable with them, so the hybrid TCU seemed like a reasonable place to begin my search for the ideal offset cam.


The Metolius Offset TCU is at first glance a carbon copy of Metolius’ Ultralight TCU. The overall size of the Offset TCU, the head design, trigger, length, sling, etc. are all identical to their counterparts on the Ultralight line. For this reason, this review touches on these design elements only when they are relevant to the discussion about offset cams. I’ve left a lot of the general discussion about the Metolius Ultralight TCU design for another review.

Functionally, the different-sized lobes are the only things that separate the Offsets from the Ultralight TCU. This is helpfully noted by the color scheme on the thumb loop and sling. Where Ultralight TCUs have a colorful plastic cover around the U-shaped base of the stem that matches the color of the sling in order to denote the size of the cam, the offsets use two different colors to indicate the two lobe sizes. As an example, a blue/yellow Offset (with one larger lobe from a yellow TCU and two smaller lobes from a blue TCU) will have a yellow band around the stem and a blue sling. This scheme is, of course, consistent throughout the line: the smaller size present on the hybrid is indicated by the color of the sling, while the larger size is indicated by the stem.


5 comments on “Metolius Offset TCU Cams”

  1. Does the offset (or non offset regular) Metolius TCU have any advantages over the mastercam other than being able to clip higher for aid? If one were choosing between the TCU and the Mastercam, what factors would u consider? In the review you mention that u can clip the TCU higher for but that the u shaped stem eliminates some placements where a single stem mastercam might fit. Are there any other factors to consider?

  2. Harpo,

    Main advantage I see to Mastercams over TCUs (having used both fairly extensively) is the single flexible stem, which makes certain placements easier. There will be shallow placements (mainly pin scars, particularly in places like Yosemite) where the U stem of the TCU will interfere with the placement. Also, Master Cams walk a lot less IME due to the flexible stem. I’ve never had cams walk more than the TCUs due to the more rigid stem. I also think in the gray-yellow sizes the Mastercam has a narrower head width (I can’t confirm this though) than TCUs, which is advantageous.

    The ability to clip the TCU a bit higher on an aid placement isn’t a big deal for me. I believe TCUs are lighter, which is an advantage, especially for a specialty piece like offsets.

    There may be very specific aid placements where an offset TCU may fit better than a single stem offset cam, but I think these are rare. One thing to consider is which direction the outside (larger) lobes face (left or right). Certain placements may fit better with the larger lobes oriented in a certain direction. This would mainly concern a wall climber and again, only applies to very specific placements. If you’re getting a 2nd set of offset cams, the TCUs could complement your other offset cams in this way.

    I’d choose Mastercams personally over the TCUs for my first set of offset cams, but that’s just like, my opinion man.

    But I’d absolutely choose offset Aliens (or Totem Basic Cams, essentially Aliens) over either in a heartbeat. The softer metal seems to ‘bite’ the rock better. The internal cam springs make for a very narrow unit, and the super flexible stem makes walking much likely. Most wall climbers seem to swear by Aliens for granite.

  3. Oh yeah, I’d double up on small regular cams before getting offsets, unless you’re aiding or climbing a lot of pin scars in a place like the Valley. Offsets are useful, and you’ll find placements for them if you look, but I think a 2nd set of regular small cams is much more useful for the majority of climbing applications.

  4. BTW, That last comment about Aliens should read that the very flexible stem makes walking much LESS likely

  5. Harpo,
    I have limited experience with the Mastercams, and even more limited experience with the off-set Mastercams, but my experience is very much in line with what Michael described above. Mastercams appeal over TCUs for many of those reasons. To build on his comparison, the longer stem of the Mastercams cam also makes it easier to get into deeper placements. True, the flexibility of the stem can reduce walking, but I have found the softer stem to be almost “floppy” under the weight of the head of the cam in the larger sizes in the range. You might find you prefer the Mastercam/TCU/Alien each in different sizes than one type of cam unilaterally.

    Michael’s assessment of the Aliens (and Totem basics) is also correct: they’re more the standard among aid climbers. A point of clarification, I believe the Fixe Alien is a carbon copy of the classic CCH version (they bought the rights to the design), whereas the Totem basic arrived once the patent had expired. While the basic is the same soft lobe metal (6061-T6 aluminum), overall structure, etc. as both the CCH and Fixe aliens, Totem introduced subtle changes to the cam sizes and the trigger wires that make them ever so slightly different. Both Aliens and Totem basic have, as far as I am aware, a 16 degree cam angle, noticeably higher than Metolius devices, that might take some getting used to if you’re used to Metolius or Wild Country cams. Check back with us for a more detailed review of the Alien and Basic cams soon.

    Finally, I completely agree with Michael that a second set of regular cams should be a higher priority for most climbers than a few off-set cams. Even for aid climbing, you’ll use the second set of regular cams more. Enjoy!

Leave a Comment