When all you need is a light layer of insulation to keep you toasty on alpine ridgelines during the shoulder seasons, reach for the Assos Trail Spring/Fall Jacket. This jacket is built to tick all of the boxes, combining lightweight insulation with a trail-focused fit, and durable comfort throughout so you can blast berms, charge steep climbs, and thread the needle through tight treelines with confidence. The Trail Spring/Fall Jacket is designed with extra attention given to the front half of the torso, keeping in mind that it takes the brunt of the abuse from the elements when you ride. For this reason, Assos decks out the front with an all-new flexible and ultra-soft material called RX Tech Melange, which offers a blend of synthetics that provides extra insulation to the core, while a tall collar on the hood offers coverage from gusts. The hood itself is built to sit snug against your noggin when its up for pre-and-post-ride warmth, but not quite slim enough to toss it on under your helmet without uncomfortable bunching, so Assos recommends reserving it for off-the-bike warmth. Moving rearwards, Assos aims for breathability on the back, employing its circular-knit Triangle fabric that you'd find in the brand's Trail jerseys. Triangle is light, flexible, and offers next-level breathability to wick away perspiration as you ride, which creates an ideal balance front-to-back, keeping in heat where you need it most, and allowing it to escape to prevent your core from overheating. The sleeves are built from Assos' RX fabric, which we like to think of as the workhorse in the brand's lineup. RX features a lightly brushed inside for a little insulation, while the elbows feature backup from dyneRope abrasion-resistant panels, so you can stand up to scuffles with tree bark and low-hanging branches. Assos wouldn't be Assos without acute attention to detail put into the fit, so we're not surprised that the Trail Spring/Fall Jacket comes dialed with trailFit. This cut is ...