The VENTRIX synthetic fill is surprisingly warm for how thin this vest packs down, and it slides right under my shell without bunching at the shoulders. I've been grabbing it for cool morning walks and it's become my go-to middle layer.
Kevin★★★★★
Wore this on a chilly morning run and it took the bite out of the air without feeling bulky. The VENTRIX fill breathes way better than I expected, and it packs down small enough to stuff in my jacket pocket.
Sofia I.★★★★★
The synthetic fill is way warmer than the thin look suggests, and it stuffs into my running pack without adding bulk. Wore it over a base layer on a 40-degree morning run and stayed comfortable the whole time.