Iron Heart - 634S Indigo 21oz

Size Guide
634 is Straight Cut and is one of Iron Hearts most Classic fits.

The Indigo 21oz Selvedge Denim is Iron Hearts signature denim. Iron Heart weave under fairly low tension to achieve an amazingly soft but super thick denim which moulds and drapes particularly well. The weft is quite slubby and the denim has a lovely 'hand made' feel to it. Fades with fairly low contrast.

  • Iron Heart classic Straight Cut
  • Super heavy but super soft 21oz indigo denim
  • Button fly and hidden rivets
  • Poly/cotton constructional stitching
  • Sanforized and one-washed (you probably can't see it), so expect little or no shrinkage (with reasonably careful washing and drying). The waist will stretch approximately one inch with wear. All other dimensions that are put under pressure will have a tendency to stretch proportionately to the stretch in the waist
  • There is no need to soak these before wearing
  • Come in one lenght, so if you need a shorter length, make a turn-up.
  • When selecting your size, please check actual measurements you need
  • Made in Japan

Model size: Height 183 cm, weight 75 kg and he is wearing size 33.




    For clothing sizing information, please read the description of the given product carefully.

    If no sizing information is available, please do not hesitate to ask us before purchasing.

    We will do our best to respond as quickly as possible.

    Have a sizing question? Let us know.


    If you are shopping for a pair of Red Wing shoes or boots, the first thing to consider with regards to sizing is this:

    Most Red Wing boots, like the popular Iron Ranger and the Beckman run big. Therefore we recommend sizing down half a size from your sneaker-size if you are purchasing Iron Rangers, Beckmans and most other Red Wing boots. However, the Red Wing chukkas (3140, 3141 etc.) are true to size. Therefore we recommend ordering your sneaker-size if you are purchasing chukkas.

    Please read the sizing-description on each style carefully, before ordering.

    Size systems

    There are many shoe size systems globally, with the US, UK, European and Japanese size systems as the most common ones. The US system also has a special category for athletic shoes.

    In Europe, shoe makers are supposed to follow the same shoe-size system. Note however, that sizes might differ between e.g. France and Germany. The sizes also aren't totally standardized, which means that shoes from different manufacturers might have different sizes, although they have the same measurements.

    Size chart

    Size charts are used to convert between different international shoe size systems. Notice that these size charts are only to be seen as guides meant to help you find your right size. Sizes and size charts may differ notably between different shoe manufacturers and brands. See the Brund shoe/boot size chart here.

    Shoe last

    In order to build a Goodyear Welted boot (e.g. a Red Wing boot) to an exact size and width, the boot is constructed around a shoe last.

    A last is used in shoemaking to give footwear its three-dimensional shape. Resembling the human foot, the last determines toe, heel and girth dimensions for fit, style and function.   

    Do notice that there is no such thing as a "normal foot" and therefore not a standard shoe last - and therefore also not a "normal shoe size". Add to that the fact that most people’s right and left feet have different measurements.

    Learn about Red Wing lasts and the Anatomy of a Red Wing at

    Shoe width

    Most shoemakers make some of their shoes in multiple widths, from narrow to extra-wide.

    US width is measured as A, B, C, D, E, EE with A as the narrowest, EE as the widest and the standard width being D.

    English made men’s shoes and boots are generally made in fittings E, F, G and H and these can quite simply be classified as follows:

    E=  Narrow
    F=  Medium
    G=  Wide
    H = Extra Wide

    Loake uses F or G and Crockett & Jones uses E and G.

    The right size

    A new pair of e.g. Red Wing Heritage boots should fit comfortably tight on your foot, with enough room to freely wiggle your toes.

    The full grain leather upper, leather footboard and cork midsole mold to your feet, creating an enduring and customized fit over time, with each wear.

    Measuring your feet

    Stand up straight on a hard surface with your heel against the wall and a piece of blank paper taped to the floor, flush against the wall beneath your foot.

    Have a friend mark the longest part of your foot (referred to as heel-to-toe length) on the paper with a pen, or measure yourself if necessary. Repeat with the other foot, as right and left sizes may be different. Use a ruler to measure the heel-to-toe length you marked for each foot.

    View the BRUND shoe/boot size chart here

    When using the chart, take note that ”CM” is NOT your heel-to-toe length in centimeter (cm), but the official shoe size (CM) 


    If you have a medium or standard foot and use US 9,5 in New Balance Lifestyle, you will probably use US 9 in Red Wing, Thorogood and Chippewa and UK 8,5 in Loake and Crockett & Jones.

    I use US 9,5 in New Balance Lifestyle and my right foot measurement is 28,5 centimeters from heel-to-toe. My size in New Balance Performance is US 10,5.

    Confused ? – then, please read from ”Size systems” again ;-)


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