FORTUX GTX - NAVY/DUNE

Name: FORTUX GTX - NAVY/DUNE
Brand: us.lowa.com
Price: 63.0 USD
Availability: InStock

Recommended for: Distance trail running and ultra-marathons, speed hiking. This waterproof, distance-focused shoe is designed for longer runs on trails in any weather conditions. Loaded with features like a speed...

Availability: Many in stock

$63.00 $210.00 (-70%)

Color: NAVY/DUNE NAVY/DUNE

Width: Medium Medium

size

Size & Fit

Hiking, Backpacking & Trail Size Guide

Measure your foot once in millimetres, then find that number in the left column of the women's, men's or kids' chart and read straight across for UK, EU and US sizes. The numbers already include the recommended toe room, so nothing needs to be added. Sizes are not standardised between brands, and a narrow shoe reads smaller than a wide one — so treat the chart as your starting point and always check the fit that suits your own foot.

NNarrow last (S) — slimmer feet
SStandard last — most feet
WWide last — more forefoot room

Women Men Kids Socks Width & Fit

Women's Footwear

Foot length 218–281 mm · UK 2.5–10 · EU 35–44.5 · US 4–12

Swipe the table sideways to see every size system.

Foot length (mm)	UK	EU	US — Trekking & Mountaineering	US — Hiking & Light Hiking
218	2.5	35	4	4.5
222	3	36	4.5	5
226	3.5	36.5	5	5.5
230	4	37	5.5	6
235	4.5	37.5	6	6.5
239	5	38	6.5	7
243	5.5	39	7	7.5
247	6	39.5	7.5	8
252	6.5	40	8	8.5
256	7	41	8.5	9
260	7.5	41.5	9	9.5
265	8	42	9.5	10
269	8.5	42.5	10	10.5
273	9	43.5	10.5	11
277	9.5	44	11	11.5
281	10	44.5	11.5	12

Two US labels, one foot. Several women's lines — hiking, all-terrain, everyday, cold-weather and tactical styles with injected soles — are labelled half a size larger in US sizing than trekking and mountaineering boots. A 252 mm foot is a US 8 in trekking models and a US 8.5 in injected-sole styles. Order by the column that matches the style you are buying.

Men's Footwear

Foot length 252–324 mm · UK 6.5–15 · EU 40–51 · US 7.5–16

Swipe the table sideways to see every size system.

Foot length (mm)	UK	EU	US
252	6.5	40	7.5
256	7	41	8
260	7.5	41.5	8.5
265	8	42	9
269	8.5	42.5	9.5
273	9	43.5	10
277	9.5	44	10.5
281	10	44.5	11
285	10.5	45	11.5
290	11	46	12
294	11.5	46.5	12.5
298	12	47	13
302	12.5	48	13.5
307	13	48.5	14
311	13.5	49	14.5
315	14	49.5	15
319	14.5	50.5	15.5
324	15	51	16

Start at your street size. Men's boots are built on UK lasts, so the UK number is the true one and the US number is a conversion (US = UK + 1). Order the same size as your everyday shoes, wear the socks you plan to hike in, and if your measurement lands between two rows, take the larger size — a boot that is slightly too long still fits, one that is too short does not.

Kids' & Youth Footwear

Foot length 128–215 mm · UK 4.5K–2 · EU 21–34 · US 5.5K–3

Swipe the table sideways to see every size system.

Foot length (mm)	UK	EU	US
128	4.5K	21	5.5K
135	5K	22	6K
141	6K	23	7K
148	7K	24	8K
155	8K	25	9K
161	8.5K	26	9.5K
168	9K	27	10K
175	10K	28	11K
182	11K	29	12K
188	12K	30	13K
195	12.5K	31	0.5
202	13K	32	1
208	1	33	2
215	2	34	3

Growing room is already in the number. Kids' sizes include 12 mm of growing room, and the US run goes 5.5K to 13K before restarting at 0.5 to 3. Measure both feet standing up and use the longer one — feet grow fastest between sizes, so re-measure before each new season rather than guessing from age.

Socks

Sold in odd EU sizes: 35, 37, 39, 41, 43, 45, 47

Swipe the table sideways to see every size system.

Sock size (EU)	US Women's	US Men's
35–36	4.5–5	—
37–38	6–7	5–6
39–40	7.5–8.5	6.5–7.5
41–42	9–10	8–9
43–44	10.5–11.5	9.5–10.5
45–46	—	11–12
47–48	—	13–14

Match your boot, not your shoe. Read the sock size from the boot size you actually wear on the trail — if your boots are a UK 8, take the sock size covering that EU range. Socks sold in odd EU numbers run every other size, so a 37 covers EU 37–38 and a 39 covers EU 39–40.

Width & Fit

Width letters, last types and how much toe room is built in

Fit	Women's width letter	Men's width letter
Narrow	A	C
Medium	B	D
Wide	C	E / EE

Last	Forefoot volume	Who it suits
Narrow (S last)	Less than a standard last	Slimmer feet
Standard	Medium — used on most styles	Most feet
Wide (W last)	More across the forefoot, plus an expanded toe box and extra room around the arch and instep	Bunions, flat feet, fallen arches, high insteps

Toe room is built in. Adult charts already include 15 mm of toe room and kids' charts 12 mm, so match your measured foot length straight to the chart without adding anything. Try boots on in the afternoon, when feet are slightly swollen, and wear the socks you plan to hike in — that combination, not the number on the box, decides whether the fit works.

How to Measure at Home

Measure standing up. Put a sheet of paper against a wall, stand on it with your heel touching the wall, mark the tip of your longest toe and measure the distance in millimetres.
Use the longer foot. Feet are rarely identical, so measure both and work from the bigger number in millimetres.
Find the row. Locate your measurement in the left column of the women's, men's or kids' chart, then read across for the UK, EU and US size.
Adding nothing on top. The recommended toe room is already included. If you land between two rows, take the larger size.

Fit Notes

Street size first: the general rule is to order the same size as your everyday shoe, in the socks you will actually wear.
UK is the true size: these boots are built on UK lasts, so UK is the reference and US and EU are conversions rather than separate fits.
Women's half-size gap: injected-sole styles (hiking, all-terrain, everyday, cold-weather, tactical) are labelled half a size larger in US sizing than trekking and mountaineering boots.
Between two sizes: size up — descending steep ground pushes the foot forward, and a boot with spare length stays comfortable where a tight one blisters.
Wide or narrow feet: a W last adds forefoot volume and toe-box room; an S last suits slimmer feet. Both are noted on the product page when a style offers them.
Heavy socks or liners: if you add a liner sock or plan a winter trip, check the next size up before committing.
Kids: 12 mm of growing room is already in the chart, so buy the size that matches the measurement rather than a size ahead.
Try them in the afternoon: feet swell during the day, so an afternoon fitting is closer to a full day on the trail than a morning one.

Shoe sizes are not standardised between brands, and sizing can vary slightly from category to category — the shape of a last also changes how large a boot feels. This guide is for sizing footwear and socks only, and all feet are unique, so a shop fitting remains the surest check.

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FORTUX GTX - NAVY/DUNE

Hiking, Backpacking & Trail Size Guide

Women's Footwear

Men's Footwear

Kids' & Youth Footwear

Socks

Width & Fit

How to Measure at Home

Fit Notes

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