The Arctery Cerium LT Size: XS Color: lime green 2020 Arc'teryx Cerium LT Puffer Jacket in Lime Green. If you know you know. This is an outdoor essential! The jacket is machine washable and has a regular fit for easy wear. The Arctery Cerium LT Jacket is perfect for outdoor activities and is a great addition to any winter wardrobe. Jacket has some stains throughout - no damage though. See pictures. The jacket is made with a solid nylon outer shell material and features long sleeves and a zip closure. The hooded jacket is perfect for the fall and winter seasons and is insulated with down material for added warmth. It was a little too tight on me, I am no longer an XS!