M's Rover Merino Half-Zip

Great material and excellent design!

I picked up the Rover Merino Half Zip to replace a basic polyester layer, looking for something that could handle cold Pacific Northwest (Oregon) winter runs while still working as a clean, versatile piece for travel and everyday wear.

This absolutely delivered! 💙

The fit is spot on—I’m 5’11”, 160 lbs with a slim build, and it hits that perfect balance of athletic without feeling restrictive. On runs, it regulates temperature exceptionally well: warm when the air is cold, breathable when the effort ramps up. Off the run, it looks sharp enough to wear straight to coffee, travel days, or casual outings without screaming “technical gear.”

The merino really shines. I wore it straight out of the package for nearly two weeks before washing, and it still smelled fresh—something synthetic layers just can’t match. After the first wash there was a very slight shrink, but nothing noticeable or concerning. I air-dried it (next to the fireplace, for what it’s worth), and it maintained its shape beautifully.

If I had one wish, it would be a subtle smartwatch slot on the forearm of either arm. The thumb holes and integrated gloves are excellent, but on colder runs I usually only use one thumb hole so I can check my watch without pulling off a glove. A small design tweak like this would honestly take this—and other long-sleeve Janji pieces—to the next level.

Overall, this is an easy favorite in my winter rotation and made it more motivating to get out in the cold weather. Premium materials, thoughtful design, versatile styling, and true performance in real-world conditions. I’m extremely happy with the purchase and would confidently recommend it to anyone running, traveling, or living in cooler climates.

This thing is super soft and comfy. I’ve only worn it on one long trail run with temps around 30F and no wind, and it was perfect!

M's Rover Merino Half-Zip

This is extremely versatile - I can use this as my only layer in high 30s, or as a 2nd layer when the temps drop into the 20s or high teens.

So far so good! I needed another midweight winter layer. I usually go pretty light. I’ve taken this out under a wind layer in low 30s no problem. On its own in the upper 30s to low 40s and it’s great and easy to dump heat with the 1/4 zip. Thumb loops are great, especially on those “gloves or no gloves?” mornings. I am confident this will hold up well given my experience with Janji. It does a good job keeping the stink at bay as well.

Worse it today as a base on a cold, windy run in Wisco. Performed beautifully. Very comfy and warm with the right kind of base underneath and
a thin shell over it.

And comfortable. Great addition to my cold weather running gear.

The merino 1/4 zip is amazing. It seems to adapt to the temp. Not too cold or warm when I wear it. Good looking too.

Purchased this for my beau and he has been using it for a few weeks now. He loves the fit and says that it keeps him warm while on the trails, without making him hot and sweaty. The merino is comfortable and hasn’t trapped odors. This will get a ton of use so we’ll see how much it can take before getting worn out! Thanks Janji for producing thoughtful and high quality gear!