The Gear Junkie Scoop: I/O Bio Merino Pilot Suit

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By Stephen Regenold

Conjuring visions of Ninjas as well as union-suit-style long underwear of yore, the Pilot Suit from I/O Bio Merino can create a “perfect body environment,” the company touts. Indeed, the head-to-ankle base-layer suit ensconces the body in thin, breathable merino wool. There's a hood, a front zipper, thumb-hole cuffs, leggings, a drawstring waistband, and a “Bombay zip” for what the company cites as “bathroom ease.”

I wore the suit, priced at $159.99, multiple days this winter. It is, in fact, quite cozy. I/O Bio Merino's wool never itched, yet it provided adequate warmth and breathability. The integrated hood is a nice touch–it's always there if your head needs a bit of extra warmth.

The “Bombay zip”–which does a U-turn in your crotch–can be dangerous. Take care not to relive a certain scene some
readers may remember from the 1998 movie There's Something About Mary. (I had a couple close calls!)

Overall, the fit and function of the Merino Pilot Suit is admirable. But one caveat: The wool is thin, and on one occasion I poked a small hole in the fabric with my thumb while roughly pulling off a leg.

In feel, the suit is like a pair of pajamas. But the wool is of high-quality–comparable to what you get from Icebreaker and Ibex Outdoor Clothing–so it breathes and does the job of a base layer.

If you can swallow the high price tag, the Merino Pilot Suit is the ultimate in coziness and convenience.

–Stephen Regenold writes about outdoors gear at

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