Smartwool PHD - Toughest Merino Socks Ever

Six months of hammer later and our Smartwool PHD Outdoor socks are still going strong thanks to their new Reliawool reinforcement technology.

Posted: 9 April 2013
by Jon

Upgrade for autumn 2012 with new, more durable impact zones, Smartwool's PHD socks have been thrashed for six months.
Heel and toe areas are obviously 'used' but nowhere near worn out. Previous versions would be threadbare by now.
Elite Fit System has stood the test of time too and is still doing it's close-fitting mid-foot gig.
Andthe cuff letting makes us smile too.

We've always been massive fans of Smartwool's lightweight PHD merino wool socks, but until last year they had a bit of an achilles heel - sorry - the high wear areas, and the toe in particular, simply wore out rather too quickly. The fit and performance were both otherwise excellent, but they just didn't last long enough.

Tougher Where It Matters

Then last autumn, Smartwool updated the design and construction and, most significantly, introduced a new technology called ReliaWool, which mixes two merino wool yarns in high wear areas to produce what Smartwool claims is a far more durable sock and without using synthetic yarns. In their publicity they say that a top US ultra-runner covered over 1000 miles in the socks with no visible signs of wear.

So when a pair of test socks arrived in September last year, we went out of our way to thrash them senseless. That meant not only using them for walking and running on the hill as often as possible - they work brilliantly with lightweight footwear thanks to the excellent 4 Degree Elite Fit system and venting zones plus strategic cushioning - but also for sustained day-to-day use.

Six Months Later

In the past, PHD socks used hard have simply rubbed through the heel in a matter of months, so we were pretty skeptical. Not any more. Six months later, and gawd knows how many miles down the lines, our test PHD Outdoor Medium Crews are still improbably completely intact. Normally we'd have rubbed through the heels by now - we have a bit of a bony spur issue there - but the ReliaWool reinforced impact points at heel, toe and under the forefoot are all still going strong.

You can see that the socks are used, but they haven't worn through or out in the places that by now wouldn't have been so much 'worn' as threadbare. There's a little bobbling on the softer ankle area and the white stripe above the heel has worn a little as well, but in the areas which matter, things are all impressively intact.

Outstanding All Round

We're massively impressed. The rest of the sock's performance has been outstanding too. The fit has remained snug and not bagged out despite repeated washing. Ankle fit is still fine with no sliding down and the socks have all the positive attributes of merino wool: good overall, non-scratchy comfort, warmth when things get moist and anti-pong properties that mean you can wear them several days running without scaring the cat.

A full review shortly, but despite the high price tag - expect to pay around £19 for a pair of the PHD Outdoor Medium Crews - we reckon these are probably the best merino wool socks we've used full stop. They're a brilliant match for lightweight outdoors footwear - other weights are available - and the added durability and multi-day capabilty does counterbalance the high-ish initial purchase price somewhat.

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