Lightweight synthetic insulated jackets are the go-to piece for wet shoulder seasons, nippy evenings at altitude and anywhere you want a little extra love from your layers. The Mountain Hardwear Thermostatic jacket, also available in a vest and hooded jacket, and in men's and women's versions, is a great layering or stand-alone piece for those occasions where you're dipping down below freezing.
The Thermostatic jacket is ultralight at just over nine ounces, thanks to MH's Thermic Micro synthetic insulation. The face is very smooth making it a terrific layering piece, no friction between layers here. Features are minimalist, elastic cuffs, a hem drawcord with dual pulls, two zippered hand pockets, and a full-length zipper flap with garage at the top. And a hanging loop. That would be it, and that's a beautiful thing.
The Thermostatic is sized a bit tight across the shoulders in the medium we tested. Stepping up to a large is a bit loose, we'd prefer a little more room in the medium. This is probably the most common complaint we have - and we hear about - when it comes to jackets. Something about samples being sized for perhaps a smaller-on-average population? Dunno, but if the Thermostatic fits you it's a winner.