冬季保暖“三件套”这样选（服务窗）

Core Viewpoint - The article discusses the increasing sales of down jackets as the "Great Cold" solar term approaches, highlighting consumer concerns over the quality and specifications of these products, particularly regarding down content and misleading marketing practices [2][3]. Group 1: Down Jackets - Consumers are advised to pay attention to the down content and avoid misleading claims by manufacturers [3]. - A qualified down jacket should meet the new national standard GB/T 14272—2021, which specifies that only four types of natural down are allowed as filling materials [4]. - The down content must be at least 50% to be classified as a down jacket, with a recommendation to choose products with a down content of 80% or higher [4]. - The total weight of the down filling should be selected based on the jacket's style, size, and intended use, with short jackets recommended to have 120-300 grams of filling and long jackets 200-420 grams [4]. - The article provides practical tips for consumers to assess the quality of down jackets, including checking for rebound speed, fluffiness, and the presence of down or dust [6]. Group 2: Thermal Underwear - The article clarifies that the concept of "self-heating" thermal underwear is misleading, as clothing cannot generate heat on its own [7]. - There are three main principles of thermal insulation in thermal underwear: static temperature retention, dynamic heat generation, and reflective heat retention [8]. - Consumers are advised to check the composition labels of thermal underwear, prioritizing materials that provide good warmth and moisture absorption [9]. - The article recommends selecting thermal underwear that meets national safety standards, with specific standards for different types of products [10]. Group 3: Insulated Cups - The article emphasizes the importance of choosing insulated cups made from food-grade materials, particularly stainless steel types [11]. - Different grades of stainless steel (201, 304, 316, 316L) have varying levels of corrosion resistance, with 201 being less suitable for food contact [11]. - Consumers are encouraged to select insulated cups that comply with national standards and to check for smooth, scratch-free inner linings to ensure safety and longevity [12].