Camping

R-value is the number that decides whether you sleep

People blame the sleeping bag when they get cold, and it is usually the pad. The ground pulls heat out of you by conduction all night, and a sleeping bag compressed flat underneath you has almost no insulating loft left. The pad's R-value is what stands between you and the dirt.

The scale is standardized under ASTM F3340, so R-values from different brands are genuinely comparable — a rare thing in outdoor gear. Roughly: R 2 and under is summer only, R 3 to 4 covers three-season use for most people, and R 5 and above is what you want on frozen ground. R-values also stack, so a cheap closed-cell foam pad under an inflatable adds its rating to the total and buys you a season for about twenty dollars.

Sleeping bag temperature ratings deserve more suspicion. The ISO/EN 13537 comfort rating is the useful one; the lower limit figure that gets printed on the stuff sack is a survival number, not a comfort number, and the difference is often fifteen degrees.

Cooler performance is insulation thickness, not brand

Ice retention claims are the least regulated numbers in camping. A rotomolded cooler holds ice longer than a cheap thermoplastic one for exactly two reasons: two to three inches of pressure-injected polyurethane foam in the walls, and a gasket that seals. Neither is proprietary, which is why the price spread between premium and mid-tier coolers is much wider than the performance spread.

What you actually control matters more than which one you buy. Pre-chill the cooler overnight, use block ice rather than cubes where you can, fill it at least two-thirds full, and keep it in shade. Those four habits move ice retention more than stepping up two price tiers, and they cost nothing.

Size follows the same discipline as packs: buy for the trip you take most often. A 65-quart cooler on a weekend for two is a heavy box of warm air.

Stove BTU is not a quality score

BTU per hour tells you how fast fuel burns, not how fast water boils. A high-output burner with a poorly designed pot support and no wind protection loses to a modest one with a good windscreen every time, because in the field almost all of your heat loss is to moving air.

For car camping, a two-burner propane stove in the 20,000 to 30,000 BTU range is the sensible default and has been for decades. For backpacking the calculation flips entirely to weight and fuel efficiency, and the question becomes how many grams of canister gas you carry per boil. Match the stove to the trip and the BTU figure stops mattering almost immediately.