The Mammut Rime Light IN Flex Hooded Jacket is a lightweight synthetic insulated jacket with stretch side panels that run up the torso’s sides and arms. The stretch panels wick perspiration astonishingly well and are perfect for dynamic activities like hiking with trekking poles, climbing, and cross-country skiing, which involve a lot of torso rotation and extension.
- Gender: Men’s (Women’s also available)
- Weight: 12.4 oz (men’s Large)
- Fit: Athletic
- Zippered Pockets: two handwarmer, one interior, sized for a smartphone
- Hood: Under-helmet, scuba fit
- Materials: Pertex Quantum Air (Shell), Polartec Grid Fleece, PFC-free
- Insulation: 40g Loopsulation (rope remnants) 100% polyester
- Packable: Yes, in handwarmer pocket
The Mammut Rime Light IN Flex is a lightweight synthetic jacket that can also be worn over a base layer starting at about 45F or less. This makes it an excellent alternative to a 200-weight fleece hoody but with better wind resistance. It’s also very similar to the Arcteryx Atom Hoodie (formerly named the Atom LT) and the Patagonia Nano Air Lite Hoody, which also combine synthetic insulation with breathable stretch side panels.
The Rime Light In Flex Hoodie has an athletic cut that borders on slim, with stretch cuffs at the wrists. It also has a fitted, non-adjustable hood that’s form-fitting, so it’s wind-resistant and retains warmth. The jacket has two climbing harness and hipbelt-compatible handwarmer pockets, both zippered, as well as an internal chest pocket, also zippered, that’s large enough to hold a smartphone.
The jacket’s primary insulation lies over the chest, shoulders, head, back, and the tops of the arms. The synthetic insulation is made with rope remnants from Mammut’s climbing rope manufacturing process. The rest of the jacket is made with thin and stretchy Polartec Grid Fleece, which wicks moisture from your torso and up along the length of your arms, where it tends to collect during exertion. The fleece portions of the jacket wick moisture wonderfully and feel damp, for example, when I’m climbing up the side of a mountain with a full load in my backpack. While the jacket is warm in cool weather, it’s not so warm that the insulated portions make you overheat and perspire.
The jacket’s external fabric is made with Pertex Quantum Air, which has a high degree of air permeability while remaining wind-resistant. The outer fabric is quiet and quite comfortable to touch, with it has a PFC-free DWR coating to repel light rain and snow.
Recommendation
The Mammut Rime Light IN Flex Hooded Jacket is a lightweight synthetic insulated jacket with highly breathable stretch side panels that run up the torso’s sides and arms. Lightly insulated, it provides good warmth and wind resistance below about 45 degrees Fahrenheit for hiking, climbing, or skiing, with plenty of mechanical stretch for dynamic movements. While it excels as a lightweight outer layer, the jacket also works well when layers under a hard shell due to its form-fitting cut and scuba hood. But the comfort of this synthetic insulated jacket is without compare in my experience: you’re not going to want to take it off, indoors or out.
Disclosure: Mammut donated a jacket for review.
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