The engine's answer

Best synthetic sleeping bag in winter nights near −12 °C, under €700

Forclaz

MT100 15 °C

The cheapest thing here, and honest about what it is.

  • Costs less than a restaurant meal
  • Perfectly adequate for warm summer nights
  • Washes without ceremony
  • Warm nights only — it has no cold-weather ability at all
  • Bulky for the warmth

Find it at Bergfreunde · Trekkinn · Decathlon · Alpinetrek · eBay (used)

Why it wins, in numbers

Forclaz MT100 15 °C is the sleeping bag the engine picked for this trip: €35 and 800 g, Comfort rating 15 °C, a 55% match on the questions asked. The kit around it comes to €675 of the €700 ceiling, leaving €25.

What the engine asked for: a sleeping bag rated to −14 °C or lower, a mat with an R-value of at least 5.5, a pack of at least 40 L, and €700 for all four; anything that falls short of these is flagged beside the item.

The kit it belongs to

Four items chosen together, not four separate winners. Swapping one moves the others.

3.44 kg on your back · €675 of a budget of €700

Tent
3F UL Gear Lanshan 2: €130, 1.10 kg, Season rating 3, 50% match.
Sleeping bag
Forclaz MT100 15 °C: €35, 800 g, Comfort rating 15 °C, 55% match. Strongest on: Fill. Flagged: Not warm enough for these nights.
Sleeping mat
Therm-a-Rest NeoAir XTherm NXT: €270, 439 g, R-value 7.3, 50% match.
Backpack
Osprey Exos 48: €240, 1.10 kg, Capacity 48 L, 50% match.

What the runners-up gave up

Each of these still leaves a kit that closes — the budget holds and the pack shuts. This is where each one lost.

  • Forclaz MT500 10 °CA cheap, cheerful summer bag that does not mind getting damp.Forclaz MT500 10 °C — €60, 900 g — gives up Price: €60 against the winner's €35. It scores 54% to the winner's 55%.

Questions this trip raises

How much does the whole kit cost?
€675 for all four items, €25 under the €700 ceiling. Prices are indicative euro list prices; the shops set their own.
How much does it weigh?
3.44 kg base weight — tent, sleeping bag, mat and pack together, before food, water and clothes. The pack is rated to carry 16 kg comfortably.
Is Forclaz MT100 15 °C warm enough for −12 °C nights?
Its comfort rating is 15 °C. For nights near −12 °C the engine requires a rating of −14 °C or lower, which it misses — nothing under this budget did, so the engine flagged it rather than leave the slot empty.

Change an assumption

This page answers one trip. Yours is not that trip — adjust the nights, the budget or the company and watch all four re-rank.

Build my kit

Specifications are manufacturers’ own published figures and prices are indicative, not live. Comfort ratings and R-values are comparable across brands but describe a standardised sleeper on standardised ground — neither is a promise about you on a particular night. Check the current spec and price with the retailer before buying.