Three things settle it: the output your heater actually delivers, the amps the pitch will give you, and how cold the van was when you opened the door. Here is the ladder of reported times, what changes from September to January, and the arrival routine that gets you there.

Fingers do not stop working on a date, they stop at a temperature, and the forecast for the car park will not tell you what it is at the top. Here is the ninety-second check that settles whether the warmers go in the gloves, plus which of the three types suits the day.

ArcticDry puts the question straight onto its own listing: are waterproof socks good for hiking? Its buyers give a more interesting answer than its marketing does.

OLPRO's listing image promises, in capital letters, that the blue bottle kills foul odours. Across the eight OLPRO reviews we could recover, not one buyer says whether it did.

Most jackets get reproofed a season late, by which point the wearer has already spent a walk cold and clammy. The beading test takes ninety seconds at the kitchen tap, and what it tells you matters more than any date on a calendar.

Most domestic electric blankets are marked for indoor, dry use and must not go on an inflatable bed, which rules them out in most tents. Here are the four checks that settle it, the months it matters in, and the two routes that are left.

Winter damp in a stored caravan or campervan is settled by ventilation first, then by whether you have mains power. Here are the signs to check, and how to lay a van up so it opens dry in spring.

Nine colours, a 2.5 litre body and a base stamped for induction, gas, electric and vitroceram hobs. What the eight reviews Amazon lets us read never mention, though, is a heat source of any kind.

Condensation in a van is arithmetic, not bad luck, and it starts on the first run of cold nights rather than on a date in the diary. Here is the morning check that decides it.

The advice you usually get is a month. The thing that actually settles it is two numbers you can check tonight: the forecast overnight low for your pitch, and the comfort rating on your sleeping bag.

Most owners of this filter straw are hoping it stays sealed forever. Eighteen of the last hundred reviewers say plainly that they have never used it, which tells you what a chunk of that 4.7-star badge is actually measuring.

The word doing all the selling here is waterproof, and the odd thing is that it mostly holds up. What the 59 most recent reviews of Mil-Tec's cover describe instead is condensation: twelve buyers found the inside wet with water the rain never put there. We counted every report before deciding we would not buy one.