Why layering beats one thick coat为什么分层比一件厚大衣好
Warmth does not come from fabric. It comes from air trapped near your body, held still by the fabric. Several thinner layers trap more still air than one thick one, which is why layering works — and it is also why a jacket squashed tight over a bulky sweater iscolder, not warmer.保暖不是靠布料本身，而是靠布料把空气固定在身体附近、不让它流动。 几层薄的能锁住的静止空气，比一层厚的还多，这就是分层有效的原因 —— 也是为什么外套被厚毛衣撑到紧绷时，反而更冷而不是更暖。
The practical argument matters just as much in Japan: everything indoors is heated. Trains, convenience stores, restaurants, department stores. You will be too hot indoors and too cold outdoors, repeatedly, all day. Layers come off. A single very thick coat does not.在日本，实际面的理由同样重要：室内全都有暖气 —— 电车、便利店、餐厅、百货公司。 你一整天会不断在「室内太热」和「室外太冷」之间来回。层次可以脱，一件超厚的大衣不行。
Layer 1 — base第一层 —— 内层
A thermal top and thermal leggings, worn against the skin. Thin, close-fitting, and the single highest-value item per gram of luggage. Buy these yourself — they are inexpensive and they are worn next to the skin.发热衣与发热裤，贴身穿。薄、贴身，而且是「每公克行李重量」价值最高的东西。 这层自己买 —— 不贵，而且是贴身穿的。
Malaysians skip this layer more than any other, usually because it looks like it does nothing. It does a great deal.马来西亚人最常省掉的就是这一层，通常是因为看起来好像没什么用。其实它作用很大。
Layer 2 — middle (the one people get wrong)第二层 —— 中层（大家穿错的那层）
A sweater — 毛衣 — or a fleece. This is the insulating layer, and it is where most of your actual warmth comes from.毛衣或刷毛外套。这是保暖层，你身上大部分的暖其实来自这里。
The common mistake is wearing a t-shirt under an expensive down jacket and expecting the jacket to do everything. It cannot. A very good jacket over a t-shirt is noticeably colder than an average jacket over a proper sweater.常见的错误是：里面只穿一件 T 恤，外面套一件很贵的羽绒服， 然后期待外套包办一切。它办不到。 好外套配 T 恤，明显冷过普通外套配一件像样的毛衣。
A sweater should fit closer than the outer jacket — it is a layer, not the outer shell.毛衣应该比外套贴身一些 —— 它是内层，不是最外面那件。
Layer 3 — outer第三层 —— 外层
What you pick here depends on where in Japan you are going and when:这一层选什么，取决于你去日本哪里、什么时候去：
- Tokyo, Osaka or Kyoto in November–December — a wool coat (大衣) or trench (风衣) with a sweater underneath is usually enough.十一月至十二月的东京、大阪、京都 —— 大衣或风衣，里面加一件毛衣，通常就够。
- Tokyo, Osaka or Kyoto in January–February — a down jacket (羽绒服), plus hat and scarf.一月至二月的东京、大阪、京都 —— 羽绒服，加帽子围巾。
- Hokkaido or Nagano in deep winter — a heavy down jacket, and snow boots. See theHokkaido guide.深冬的北海道或长野 —— 厚羽绒服，加雪靴。 请看北海道那篇。
- Skiing or a snow park — a waterproof shell (衝鋒衣) rather than down, because you will be sitting and falling in wet snow.滑雪或雪park —— 用防水的衝鋒衣，不要用羽绒服， 因为你会坐在湿雪上、也会跌进去。
Rule of thumb: if you will be outdoors for hours at a time, add a layer rather than a thicker coat. If you will be in and out of shops and trains all day, you want layers you can remove without stopping.简单原则：如果会连续在户外待几个小时，加一层，而不是换更厚的外套。 如果整天进出商店和电车，你要的是随手就能脱掉的层次。
So what do you rent?那到底该租什么？
Layers 2 and 3 — the sweater and the outer jacket. Layer 1 you buy. That split is not us being modest about what we rent; base layers are cheap and worn against the skin, and there is no sense renting them.第二层和第三层 —— 毛衣和外套。第一层自己买。 这样分不是我们客气，而是发热内层便宜又贴身穿，根本没有租的道理。
Rent three items or more and the rental on one hat or scarf is waived. Categories and warmth guidance are on the collection page; sizing is on thesize guide.租借 3 件或以上，可免其中一件的租金。 类别与保暖建议在冬装系列，尺码请看尺码指南。