Everything worth knowing about Supreme Thermal is below, starting with the part that changes what you buy. Warmth comes from trapped air, which is why loft matters more than thickness or weight. Down is warmer for its weight; synthetic keeps insulating when wet and costs less. Fibre content tells you more than price. Look for the percentage, not the word cashmere. The groups below run from the decision that matters most to the ones you make afterwards.

What decides this is fibre, gauge and how well it holds shape. Everything else is preference. Two from the first group show the range: Ronny Kobo's Krystal Sweater at $348, and Cynthia Rowley's Ziggy Knit Tank at $245. The first is the considered buy; the second is the one to start with. Fibre content tells you more than price. Look for the percentage, not the word cashmere. A tight gauge holds shape; a loose one drapes and eventually grows. A higher price mostly buys materials and finishing, and occasionally it buys nothing at all.

Tuck the front hem only. It reads as considered rather than fussy. From the second group, cynthiarowley.com's Metallic Knit Crewneck ($195) is the one that earns its place, because it works in more than one context without being restyled. The third group is smaller and deliberately narrower, knits, for the decisions you make after the main one. None of this needs the whole group. One piece from each is usually enough.

There are 20 knits here from 16 brands, $81 to $440, all in stock when this was written. We would not buy all of them, and neither should you. Organic Basics's Weekend Crop Hoodie at $81 is the low-risk way in, and otteny.com's Cashmere Felted Stole Cedar Green at $440 only makes sense if this is a category you already use constantly. Read as a set, they get you close to Supreme Thermal without any single purchase being compulsory. Nothing here is included because it is famous, and price is not used as a proxy for quality anywhere on this page. If you take one thing away: pay for the thing that touches your body and economise on the thing that sits on top of it.