What Our Gearhead(R) Experts Are Saying:"I use this as my go-to insulated layer when the air is cold, but I still need to move fast-there's enough warmth from the reflective lining and synthetic fill for solo wear, and it's trim and smooth enough to slide under a shell on stormier days."We pull on the Columbia Terwilliger Trail Heat Seal Jacket when the air feels sharp, but our plans keep us outside, from quick walks around the block to long days exploring new trails. Columbia's Omni-HEAT Infinity lining reflects our body heat back toward us, helping this midweight insulator feel warmer than its slim profile suggests as we wait for coffee, scrape windshields, or lace up at the trailhead. Heat Seal construction creates smooth, stitchfree baffles that trap warmth and slide cleanly under a shell when the weather really turns. Once we start moving, the Thermarator recycled synthetic insulation keeps performing even when mist, light snow, or road spray enters the picture. Zippered hand pockets stash keys and a phone, while giving our fingers a quick warmup, and binding at the cuffs helps shut out drafts. With a drawcordadjustable hem to finetune the fit and a lowbulk build that packs easily into a bag, the Terwilliger Trail Heat Seal Jacket is ready to live by the door all season long.