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Luna Oso 2.0 RETRO


Some people just can’t stop loving a great thing, or want to love something new that is old. What can we do for you? Easy! The RETRO line of LUNAs uses our tried-and-true PRE-WING lacing system known in the day as ATS (All-Terrain-Strapping) laces. You can have’em just like dad did in 2012!

NOW Re-Introduced, the old favourite is back and is now called Oso 2.0 Retro.

This rugged sandal is designed for real hardcore trails. Barefoot Ted has put the original Oso through rigorous testing on many trails including the Leadville Trail 100, where they performed exceptionally well.

The Luna Oso 2.0 RETRO (Bear en Español) is a revelation in trail sandals with a tough, rugged sole and protective midsole, topped by non-slip MGT footbed. An all new aggressive tread pattern, Vibram Megagrip, makes the Oso 2.0 RETRO a great option for off-road running and adverse weather conditions where maintaining your footing is essential. This sandal can handle most advanced trails and wet conditions, whether running or walking.

The Oso 2.0 RETRO uses the NEW Performance Laces 2 and Tech Strap which have been so successful in testing.  If you need more strapped-down security for technical trails, mud/obstacle runs, MovNat adventures, wilderness walkabouts, Fuego y Agua Ultra-ing... this strapping system was developed with you in mind.

The Oso 2.0 RETRO takes the edge off all those sharp rocks that otherwise can bruise and tenderize the bottom of your feet. The sole of this sandal is a 13mm with a 4.5mm Vibram Megagrip outsole which is lightweight, durable, and has an seriously aggressive tread pattern.

  • How does it compare to the other sandal models?

    • The Oso Flaco is our lightest, thinnest (7mm) model. Great for off or on road running or casual wear, and moulds well to your feet.
    • The Mono 2.0 is our most versatile sandal. It's fairly thick (11mm), but also light weight and mouldable. It has some grrrrreat traction for trail running, but not so much that it can't be used for road wear.
    • The Oso 2.0 (13mm + 4.5mm lugs) is secure and rugged, but also our heaviest, least mouldable option. If you need a tough, long-lasting sandal for rocky terrain or a trail ultra marathon, the Oso 2.0 is for you.
    • The Origen 2.0 (13mm) and Origen Flaco (10mm) are lightweight robust alternatives to the Oso 2.0.  They have less aggressive tread than the making them ideal for distance road and trails. 
    • Made in Vietnam designed in Seattle, USA.
      Weight: 9.2 oz (single sandal, men's size 8UK)
      Thickness: 13MM base + 4.5MM lugs
      Sole: Vibram® Megagrip Outsole + Vibram® Midsole
      Footbed: MGT (Monkey Grip Technology)
      Laces: Performance Laces 2.0 *Patented With Tech Strap


    • The Oso 2.0 Retro comes with our secure and comfortable Performance 2 laces. The Performance 2 laces include our LUNA Plug System, which consists of a soft, tubular nylon between the toes and a flat plug under the outsole for extended wear protection.

      The remainder of the laces are made up of a 5/8" climbing-grade tubular nylon with an extra padded heel strap, making the sandals easy to slip on and off. The all new buckle at the top of the foot allows for simple adjustments thanks to the ability to tighten and loosen the buckle and slide the strap up and down the toe strap. 

      All sandals with the MGT footbed and Performance 2 laces will be made with vegan padding in the heel strap, making them entirely vegan!

      **Note: The Performance 2 laces are not interchangeable with other laces at this time.**

      ALL NEW MODELS include the tec strap which assists the heel strap in staying firmly in position without offering any support.

    • We stand by all products we offer at LUNA.

      If you are not satisfied with one of our products or if they ever fail you, return them to us for a replacement, (partial or full) refund, store credit or repair.

      A reasonable charge will be assessed for damage due to wear and tear or for repair.

      For any production defect that you might encounter on your LUNAs, you have the MoonRock Guarantee. For example, your LUNAs should never delaminate on the sole or have its buckle or plug break during their lifetime unless they are purposefully abused.

      Even though many LUNAtics put thousands of miles on their LUNAs, it is hard to give a definite lifetime. How a LUNA wears will vary from person to person, model to model depending on the intended use, gait, weight, load, terrain, running form, and climate.

      These would void your MoonRock Lifetime Guarantee: Intentional misuse. Returns on products which show normal wear and tear but no defect. Any damage incurred from improper cleaning or self repairs (e.g. cutting or removing tags, cutting the soles of your sandals).

    Related Items

    LUNA Sizing
    Once you've determined your size, you can double check it by clicking the corresponding Printer Iconand printing out a template.
    When printing our copyrighted PDF templates, make sure the "Scale" in the Print Window is set to 100% or the template won't be accurate.
    If using the Chrome browser, make sure the "Fit to page" checkbox is UNCHECKED.
    After you print out the template, also double check the scale by comparing a ruler to the ruler that prints on the template.
    Toes should be close to edge, but not hang over. Want our opinion? Send a photo of your foot on the template 
    The biggest issue people have is not having the template accurately printed, so double check twice. ;-)
    Simplest way to measure your foot is:  Heel against wall, mark on ground to longest toe, measure in cms, compare to chart below.



    Your Foot



    Mens & Womens


    LUNA Mens US LUNA Womens US the actual width of our sandal in centimeters Print
    21.9 - 22.2 3 4 6 9.2 Printer-icon
    22.3 - 22.6 3.5 4.5 6.5 9.4 Printer-icon
    22.7 - 23 4 5 7 9.6 Printer-icon
    23.1 - 23.5 4.5 5.5 7.5 9.8 Printer-icon
    23.6 - 23.9 5 6 8 10 Printer-icon
    24.0 - 24.3 5.5 6.5 8.5 10.2 Printer-icon
    24.4 - 24.7 6 7 9 10.4 Printer-icon
    24.8 - 25.2 6.5 7.5 9.5 10.55 Printer-icon
    25.3 - 25.6 7 8 10 10.7 Printer-icon
    25.7 - 26.0 7.5 8.5 10.5 10.85 Printer-icon
    26.1 - 26.4 8 9 11 11 Printer-icon
    26.5 - 26.8 8.5 9.5 11.5 11.15 Printer-icon
    26.9 - 27.3 9 10 12 11.35 Printer-icon
    27.4 - 27.7 9.5 10.5 12.5 11.5 Printer-icon
    27.8 - 28.1 10 11 13 11.7 Printer-icon
    28.2 - 28.5 10.5 11.5 13.5 11.85 Printer-icon
    28.6 - 29.0 11 12 14 12 Printer-icon
    29.1 - 29.4 11.5 12.5 14.5 12.2 Printer-icon
    29.5 - 30.1 12 13 15 12.4 Printer-icon


    LUNAcito Sizes (Not available in the UK so ask us)

    Length LUNAcito Sizes Print
    19cm K12
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    Hey LUNA Monkeys, I don't fit into any of your standard sizes, what can I do?
    Contact us on and we can see if there is a special make up sandal that could be available to your foot spec.