NEMO Roamer Self-Inflating Mattress reviewed

The NEMO Roamer is a 10cm self-inflating foam mattress for car camping, with a stretch polyester top, an R-value of 7 and four sizes from a 64cm single to a 132cm double. NEMO has no sterling web shop, so UK buyers go through retailers, where the recommended price starts at £239.99 for the Single. Its strongest card is control: a two-valve system that lets you set the firmness more precisely than most foam mats allow.

Four sizes

Weights below are NEMO’s packed figures; prices are the recommended retail prices shown by Ultralight Outdoor Gear at the time of writing (October 2026). That retailer was selling every size about 10% under these prices, with no end date given.

The Single and Single Wide carry toggles and loops so that two can be joined into a double. Two Singles side by side give 128cm, almost the width of the Double Wide, and each sleeper keeps their own foam core, so a partner’s turns travel far less than across one shared surface.

Valves and Flow Core

The Roamer gives filling and emptying a valve each. A flush Laylow valve lets air out in small, controlled amounts, so you can soften the mat a little at a time instead of opening a valve and guessing, and a separate one-way dump valve empties it fast in the morning. Inside, NEMO’s Flow Core channels run both across and along the foam, which NEMO says speeds up inflation and deflation and lets the mat pack smaller than its rivals. The stuff sack, called Vortex, doubles as a pump sack for topping up and as a dry bag.

Insulation at R 7

R-value is the measure of how well a mat blocks heat loss to the ground, and the higher the figure, the warmer you sleep. Ultralight Outdoor Gear lists the Roamer at 7.0 under the ASTM F3340 standard, the lab test that measures heat flow through a camping mattress between a hot and a cold plate so figures compare across brands. That matches the Therm-a-Rest MondoKing 3D and sits below the Exped MegaMat’s 8.1, and it is warm enough for UK winter camping on cold ground.

Fabric and durability

Top and bottom are recycled polyester, bluesign approved according to the retailer, with a stretch knit on top that feels softer than the slick shell of an air pad. For buyers outside the USA and Canada, NEMO’s international warranty gives five years against manufacturing defects. The lifetime cover advertised on NEMO’s American site does not apply to UK purchases. Ultralight Outdoor Gear delivers free with tracking across the UK and takes returns within 30 days.

Roamer against the MegaMat and MondoKing

Against the Exped MegaMat, the Roamer Single is 13cm narrower and less warm, but it packs to 35cm long rather than 79cm and costs less than the MegaMat’s £290. The Therm-a-Rest MondoKing 3D Large is cheaper still and 1cm deeper, but it rolls to 66cm, almost twice the Roamer Single’s length.

We would choose the Roamer if you are particular about firmness, if boot space is tight, or if two of you want separate mats that join. It is the wrong buy for walkers, since even the Single weighs about 2kg, and for anyone who puts warmth first, where the MegaMat’s 8.1 leads.