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New SATRA fitting aids

Considering the importance of accurate sizing and the help available to achieve this key sales tool.

by Tom Bayes

With the continued growth in e-commerce, communicating the correct sizing of footwear to consumers has never been more important. Customers are generally ordering sizes based on previous experience and, in some cases, multiple sizes. Footwear that does not fit correctly is returned, and these returns can represent a significant amount of stock in transit, generating many additional costs – as well as increasing the carbon footprint.

Within the popularity of online buying, sizing has become a very important issue. In this article, we consider the challenges posed by the variety of footwear sizing systems currently in use and how a robust fitting process using fitting aids can increase consumer satisfaction.

The online ordering process relies on the consumer knowing the size of his or her feet. There are many sites on the internet which claim to allow the consumer to make such measurements, but not all will provide an accurate figure. The obvious measurement to take is the length of the foot in millimetres, known as the ‘Mondopoint’ sizing system, and which is the only sizing system based on the length of the foot.

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The return of poorly-fitting footwear purchased online can involve considerable expense for the supplier

Another problem…

There is, however, an additional complication. Many manufacturers will not own their own lasts, and those that do will be graded to a particular sizing system. For example, consider footwear marked for retail with several different sizing systems – Paris Points, UK, US and Mondopoint – as is commonly the case. Without very tight controls (and even assuming that the last is correct), these sizing systems do not directly and simply convert from one to another. One of the marked sizes is the actual size of the footwear and the system used by the manufacturer to create the size grades of the last. All the other marked sizes on the footwear are estimations on the conversion from one system to another. For instance, a UK 10 is actually almost exactly an EU 44. However, a UK 9 is somewhere between an EU 42 and 43.

This introduces a great deal of confusion and depends heavily on perspective. If a consumer normally purchases using the EU system and orders a size 42 which is made on a UK 9 last, the small amount of extra length would not normally be an issue. A consumer who wants a UK size 9 and receives an EU 42 made on an EU 42 last will probably find the footwear a little short. The correct conversion also relies heavily on whether or not half sizes and different fittings are available.

There is an additional complication – Mondopoint is the only system based on foot length. The grade for the others is based on the last length. For a conversion system to work, it is necessary for everyone to agree on what length of foot fits a particular last. Simple research will show there are a wide variety of opinions offered by various retailers, even with odd conversions being suggested – such as UK size 10 being the same as EU 43/44. These conversions are often specific to a brand’s market. ‘Comfort’ brands will often offer a more generous fit (for good reason), and individuals will have their own preference of fit. However, this is very different to receiving goods which simply do not fit because of incorrect size marking.

The wrong size

The most extreme case occurs when the lasts for manufacture have been incorrectly sized – a situation which happens surprisingly often. Lasts may be selected and mistakenly sized using a measuring tool specifically designed to measure foot length. This results in footwear being marked two sizes above their actual size and, in addition, the size profile for production is completely skewed.

These conversions often cannot simply be made by looking up figures on a table – the footwear needs to be fitted. The accurate fitting of footwear is, of course, a highly skilled profession but, by taking this action, sizes can be determined after the last is slipped. This will ensure that shape retention levels, materials stiffness, structure (or lack of) will form part of the fitting process, and an accurate size conversion can be made. It is still very important, however, to know the details of the original last which is the common ancestor of all conversions and future modifications.

Size conversions are often confusing

The following are genuine examples of size conversions found on footwear labels. In each case, one of the sizes is accurate, and the others are compromises.

Label 1:
US men: 10 UK: 9.5 EU: 44 JP: 280 CHN: 270

Label 2:
US men: 10.5 UK: 9.5 EU: 44 JP: 285 US women: 12

During development, footwear is fitted on human models who will have their foot dimensions measured and confirmed prior to the fitting process. It is very unlikely that they will have perfect feet, and even those that measure exactly to a particular size will change during the day. Even so, this is a common way of sizing footwear. Of course, footwear, except in the bespoke industry, is not designed to fit just one person – it is to fit a percentage proportion of the population. Ideally, several human models of differing dimensions will be used in order to cover the variation in the population of those considered to be the same size. The size of that percentage will heavily influence the sales of the footwear. This emphasises the importance of knowing where the human models fit in terms of the population, which can only be determined with accurate contemporary population data.

There is an additional level of complication when it comes to children’s footwear. Fitting staff must be screened beforehand and children have to be supervised. Increasing legislation often means the children can only take part in product development process if the parents opt in. Children also grow, so if changes are made to lasts and patterns, the ideal foot is no longer available.

Foot size data

SATRA currently has the most up-to-date global foot size data available, which can be further broken down by such aspects as demographics and age. It is now possible to have an adult human model scanned, the scan measured and the position determined within population specific or global data to give perspective on exactly where the model lies within the modern population. If the actual last is available, this can be automatically assessed with the new SATRA Digital Last Assessment service and its dimensions compared against population data. The effects of small changes in dimensions can be determined and the subsequent increase in population coverage estimated, which will directly affect sales volumes.

SATRA has a global footwear dimensions database of tens of thousands of scanned feet

SATRA is in the process of developing a straightforward fitting aid tool to address some of the difficulties posed by the current reliance on human models. These aids are, in effect, precisely-dimensioned artificial feet that can be easily inserted into footwear and feel like real feet. SATRA’s fitting aids are not designed to replace skilled fitters and their subjects, but to allow footwear to be fitted on a standard range of feet. These feet will never change and will always be available. The same feet can be therefore used in different locations around the world – something that is not practical with human models. This particularly applies to fitting children’s shoes where, as already mentioned, the model is often only available for a short period of time.

SATRA’s new fitting aid features a simplified skeletal structure buried within a soft flesh-like material

The fitting aids are designed to represent a foot in such a way that it can be used in exactly the same way as a human foot. The design has a simplified skeletal structure buried within a soft flesh-like material. When inserted into the footwear, the fitter can feel such important elements as the joint points and the big toe, and make a judgement regarding the fitting of the footwear.

The most important part of the design is the shape of the foot itself. This is derived from our global footwear dimensions database of tens of thousands of scanned individuals. Initially, standard sizes will be offered, where the shape is created from an amalgamation of three-dimensional foot scans and are designed to accurately represent the average foot. Depending on demand, feet can be designed to be very specific to the market for which the product is destined – demographically and geographically. Specialist feet could be produced for certain purposes, age ranges and specific countries – in fact, for any situation where data is available.

In the future it will be possible to have duplicates made of your own human models’ feet to allow for periods where they are not available, and also for use in locations to which they cannot travel.

How can we help?

Members interested in more information regarding SATRA global footwear data, digital last assessment or the fitting aids are invited to email for further information.

Publishing Data

This article was originally published on page 36 of the June 2020 issue of SATRA Bulletin.

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