The Verdict: Most Owners Should Skip the Hest
The M1 doesn't come with a mattress. Tune offers the Hest Dually Wide as a +$629 add-on, and it's a good mattress. But it's also the most expensive way to solve a simple problem: putting 4 inches of comfortable foam on a flat rectangle. After pricing every realistic option and reading what owners actually sleep on, here's the honest take.
| Path | Cost | Best for |
|---|---|---|
| Custom-cut foam + cover value winner | ~$100–$200 | Almost everyone. Exact fit, you pick the feel, ships to your door |
| RoamRest Pioneer best turnkey | from ~$485 | Want a finished premium mattress but not the Hest tax. Same foam as DIY, plus convenience and returns |
| Hest Dually (via Tune) | $629+ | You want zero sourcing, factory fit on pickup day, and the inflatable feel |
The quick decision:
- Want the cheapest perfect-fit mattress? Order custom-cut HD36 foam at your exact platform size and add a zippered cover. About $100–$200 all in. Full how-to below.
- Want a finished premium mattress without paying Hest prices? A RoamRest Pioneer custom-sized to the M1 starts around $485, with a washable cover. It's a legit US-made mattress, but note it runs firm, so if you're a side sleeper, order the soft version.
- Hate sourcing anything and want it handled at the factory? Buy the Hest through Tune and move on. It's the priciest route, but it's done.
What I chose for my own M1: full DIY, over both the Hest and the RoamRest. I take delivery July 21, 2026 with the King Bed Extension, and after pricing every option I'm building my own.
The RoamRest is a legit US-made mattress (North America Mattress Corp, 20+ years in Oregon, CertiPUR foam), but it's the same custom-cut foam I can order from Foam Factory plus a cover. The ~$235 premium buys convenience and a return policy, not a better bed. The "exchange it if the firmness is wrong" safety net is just them mailing you different foam, which a $40 topper replicates.
I can build it twice and still land at RoamRest's price, so a firmness miss is a built-in second chance, and lightly used foam resells easily in Denver. I'm a back-and-side sleeper, so I'm layering a firm base with a softer top instead of one firm 4" slab. I haven't slept on it yet; the real verdict comes after install.
Tune M1 Mattress Dimensions
The M1 has two platform sizes depending on truck bed size. The mid-size platform (Tacoma, Ranger, Colorado) is 60" wide × 72" long. The full-size platform (Tundra, F-150, Ram 1500, Silverado) is 60" wide × 78" long. These are east-west platforms; your head and feet go across the width of the truck.
One thing to factor in: on the standard platform you sleep across the 60" dimension, so 60" is effectively your bed length. That's shorter than a standard mattress, so anyone 6 feet or taller will find it tight lengthwise. The full-size platform's extra 6" doesn't fix this, since you're still sleeping across the 60" axis. How tight it feels also depends on the truck: one owner noted that "bed widths vary by rig, so sleeping east-west is different in a full-size rig vs. a Tacoma." Lie down in your variant before you decide.
The King Bed Extension is the fix for taller owners. It adds a platform that slides out over the cab, letting you sleep north-south (head over the cab) and fully stretch out. It changes the mattress decision enough that it gets its own section below. If you're skipping the extension, the standard platform takes one continuous mattress and the rest of this guide is simpler for you.
How the platform compares to standard mattress sizes:
| Mattress Size | Dimensions | Fits Mid-Size M1? | Fits Full-Size M1? |
|---|---|---|---|
| M1 Mid-Size Platform | 60" × 72" | — | — |
| M1 Full-Size Platform | 60" × 78" | — | — |
| Standard Twin | 38" × 75" | Too narrow (22" gap) | Too narrow (22" gap) |
| Twin XL | 38" × 80" | Too narrow (22" gap) | Too narrow (22" gap) |
| Short Queen | 60" × 75" | 3" trim needed (or 3" gap) | 3" gap at foot, usable |
| RV Short Queen | 60" × 74" | 2" trim needed (or 2" gap) | 4" gap at foot, usable |
| Custom cut foam | 60" × 72" or 60" × 78" | Perfect fit | Perfect fit |
The platform is a flat rectangle with no cutouts. The M1 ships without a mattress in the base price. Tune offers a Hest Dually Wide as a paid add-on (+$629), or you can source your own. Most owners go custom-cut foam from a supplier like Foam Factory for $80–$130.
King Extension & the Over-Cab Gap
Skip this section if you're not getting the King Bed Extension. The standard queen platform takes one continuous mattress and you're done.
The King Bed Extension is a platform that slides out over the cab each night and tucks back during the day so the space stays usable for the camper. Because that section physically slides, the mattress over it has to be its own separate piece that travels with the slide. You can't bridge a slide-out with one rigid mattress.
This is where the Hest setup gets surprisingly complicated. The Hest Dually folds in half, so even the standard queen has a seam down the middle. Add the king extension and you're stacking a third piece (the separate Dually Extend pad, $289) on top of that. Three foam segments, two seams for a king sleeper. A custom-cut setup does the same job with two clean pieces: one for the main platform, one sized to the slide.
Two more things king-extension owners learn from experience. First, sleeping north-south means the head of the bed is over the cab and can be a long reach — one couple rigged a small pulley-and-bag system to reach gear up there. Second, the extension is what makes the M1 work for taller people: 6-footers who skip it often end up sleeping diagonally on the 60" platform to stretch out. If you're tall and camping with a partner, the extension is usually worth it.
Thickness & Headroom: The Key Tradeoff
Mattress thickness directly impacts how much headroom you have when sitting up in bed. With a 4" mattress installed (the most common owner choice), there's 30.5" of clearance between the top of the mattress and the ceiling of the pop-top. How thickness affects that headroom:
| Mattress Thickness | Sitting Headroom | Assessment |
|---|---|---|
| 3" | ~31.5" | Most headroom, but less comfortable sleep for most people |
| 4" (most common) | 30.5" | Community sweet spot: comfortable sleep + generous headroom |
| 5" | ~29.5" | Still workable for most: noticeably better sleep quality |
| 6" | ~28.5" | Starts to feel low for taller campers sitting upright |
| 8"+ | ~26.5" or less | Most people find this uncomfortably cramped for sitting |
Mattress Types: What Works in the M1
Memory Foam
Most popular choice for M1 owners. Conforms well, compresses for loading, and is available in custom sizes. Sleeps warmer than latex, which can be a pro or con depending on your typical climate.
Latex Foam
More breathable than memory foam, bounces back quickly, and is naturally more durable. Heavier than memory foam of the same size. High-quality latex is noticeably more comfortable but a lot more expensive.
Hybrid (Spring + Foam)
Good comfort but hard to find in custom sizes. Springs add weight. Generally not the first choice for a truck camper application unless you're coming from a specific preference.
Standard RV / Camping Pads
Lightweight option but typically compromises on comfort for extended use. Fine for occasional overnights; most full-time or regular M1 users upgrade quickly.
Top Picks: What M1 Owners Are Sleeping On
Also worth knowing: the ROAM Adventure Co. Memory Foam Mattress ($359 per 78"×30" pad) is a different brand that daisy-chains pads together. Two pads make a 60"-wide surface, but that runs ~$718, more than the Hest and well above a custom cut. Its real edge is insulation: an R-10.8 value that's a real plus for cold-weather sleepers. Worth a look if winter warmth matters more to you than price.
DIY: Build Your Own M1 Mattress for ~$200
This is the path I'd recommend to most owners, and the one that exposes how much you're paying for the Hest badge. You order foam cut to your exact platform dimensions and add a cover. No compromise on fit, no mattress that's an inch too wide, and you choose the firmness instead of accepting whatever the brand picked. Total cost lands around $100–$200, versus $629+ for the Hest.
The one knock on DIY is that custom-cut foam is final sale. Here's the reframe that makes it a non-issue: at ~$150 a build, you can get the firmness wrong once, rebuild, and still spend less than a single RoamRest, and lightly used foam resells easily. Your "return policy" is just cheaper. Buy the top layer as a separate piece and you can tune the feel for $40 without rebuilding anything.
Want the Hest's soft-top feel without the cold problem? The Hest is a soft memory-foam top over a firmer base, about 3.9" total. Rebuild that same soft-top/firm-base structure with cold-stable materials: a 3" firm HD36 base plus a 1" soft top. For the top, super-soft PU is the lightest and cheapest, latex the most durable, and both stay soft in the cold, unlike memory foam. That's the whole point: HEST markets its foam as staying soft "regardless of temperature" but publishes no test data, and the one in-depth independent cold test (CleverHiker, 60+ nights down to -14°F) found it firms up below about 10°F, like any memory foam. So skip a memory-foam top if you cold-camp.
Step 1 — Order the foam, cut to size
From your chosen supplier (see the vendor ranking below), order:
- Foam grade: HD36 high-density is the community standard, supportive and long-lasting, and it doesn't cold-stiffen like memory foam. The firmer HD36-HQ is the higher-quality version. Match it to how you sleep: a firm 4" HD36 slab is great for back sleepers but too firm on the shoulder and hip for side sleepers. If you sleep on your side (or both, like me), layer it, a ~3" firm HD36 base with a ~1" softer top (latex or memory foam), or add a topper. Side sleepers want medium, not firm.
- Size: 60" × 72" (mid-size) or 60" × 78" (full-size). Measure your own platform first; interior dimensions vary slightly between builds.
- Thickness: 4" is the standard and keeps ~30.5" of sitting headroom. One honest caveat: dedicated side sleepers often bottom out at 4" on the M1's hard platform and are happier at 5–6" (trading ~1–2" of headroom). Back and stomach sleepers do fine at 4". It ships compressed, so it's easy to get into the camper.
Expect roughly $100–$160 for a layered 4" cut, and 7–14 business days if you ship (a local shop is often same-week).
Step 2 — Add a cover (you don't need to sew)
The foam ships bare, so it needs a cover to stay clean and last. Three honest options, cheapest to nicest:
- Buy a zippered cover (easiest). Suppliers like Foamma and Foam N More sell water-resistant zippered covers cut to your exact dimensions for roughly $40–$80. Order it with the foam and you're done. This is the recommendation for most people.
- Use a fitted sheet (cheapest). A Short Queen RV fitted sheet (60" × 75") slips right over a mid-size cut. Zero extra cost if you already have one, though it offers no spill protection.
- Reuse or sew one. An existing self-inflating pad's cover (an Exped, for example) can sometimes be repurposed, or a local upholstery shop will sew a custom zippered cover. More effort, but you control the fabric.
Step 3 — For king-extension owners, cut two pieces
Order two cuts: one for the main platform and one sized to the over-cab slide so it sits flush. Then run a single oversized fitted sheet over both to hold them together as one surface. Two clean pieces, one seam, for a fraction of the Hest's three-segment king setup.
Step 4 — Add an airflow layer (do this)
Foam on a solid, cold platform traps condensation underneath and grows mildew. Put a thin airflow mat (a HyperVent-style spacer or 3D mesh, ~$40–$60) or slats under the mattress, and use a breathable cover, not vinyl. It's the one camper-specific step home-mattress guides skip, and M1 owners have woken up to moisture. Cheap insurance.
Where to buy the foam — the honest ranking
Not all cut-to-size vendors are equal. In order of what I'd actually do:
- A local foam / upholstery shop (best). You get to feel the firmness before you buy — which matters most if you and a partner sleep differently (side vs. stomach vs. back), since "firm" and "soft" are famously subjective. You also get true density, covers sewn in one stop, and you support a local business. Search "upholstery foam" or "custom cut foam" in your city. Some local mattress shops will build the whole thing with a return policy, which erases the "final sale" worry entirely.
- Reputable mail-order: FoamOrder, Foam N More, or FoamSource cut foam and latex to size for DIYers, with stronger quality reputations.
- Foam Factory / Foam by Mail (cheapest, with an asterisk). It's the same company under two names, and it's the budget pick — but owners repeatedly measure its foam under the advertised density (a rated "2.8 lb" HD36-HQ often tests ~2.2–2.5 lb), so it's lighter but also softer and less durable than spec. Fine for occasional camping; if you'll sleep in the M1 a lot, spend up on a true HR base or buy local.
Don't glue the layers; keep it modular. Spray-adhesive welds the soft top to the firm base and kills the cheap-refresh advantage. Instead, stack the two layers loose inside one snug zippered cover: the cover holds them together, and when the soft top packs out you unzip and drop in a fresh ~$40 layer. A couple of peel-able Velcro tabs stop any creep on a sliding over-cab piece. The Hest's bonded, sealed core can't do this. When its top wears, you replace the whole $629 mattress.
| DIY component | Cost |
|---|---|
| 3" firm HD36 base + 1" soft top, cut to size | ~$100–$160 |
| Water-resistant zippered cover (custom cut) | ~$40–$80 |
| Second layered piece (king-extension owners only) | ~$50–$90 |
| Airflow mat / spacer under the mattress (recommended) | ~$40–$60 |
| Typical all-in total | ~$180–$320 |
Copy-paste order sheet (exact M1 sizes)
Order HD36 high-density foam cut to size. The generic custom-mattress page defaults to basic conventional foam, so order HD36 from Foam Factory's HD36 cut-to-size page instead. Want a plusher top? Add a 1" latex topper rather than memory foam.
| Your setup | Foam to order (each piece, 4" thick) |
|---|---|
| Mid-size, standard platform (Tacoma, Ranger, Colorado) | One piece: 72" × 60" |
| Mid-size + King Bed Extension | Two pieces: 72" × 60" + 72" × 20" |
| Full-size, standard platform (Tundra, F-150, Ram, Silverado) | One piece: 78" × 60" |
| Full-size + King Bed Extension | Two pieces: 78" × 60" + 78" × 20" |
| Cover (any setup) | One zippered cover per piece, plus one oversized fitted sheet over both |
Sheets & Bedding for a 4" Mattress
This trips up nearly every new owner, because a 4" mattress is far thinner than the deep home mattresses sheets are built for. Standard fitted sheets have deep pockets that bunch up and slip off a thin foam pad.
What works:
- Short Queen RV fitted sheets (60" × 75") are made for shallow RV mattresses and are the closest off-the-shelf match for the mid-size platform. Search "RV Short Queen sheets."
- 100% cotton in an RV Short Queen set is the most-requested option from owners who don't like synthetic feel. If you can't find the size in the material you want, a local seamstress can run a fitted set to your exact 60"×72" or 60"×78" dimension cheaply.
- King-extension owners: a single oversized fitted sheet pulled over both the platform piece and the over-cab piece doubles as a connector, keeping the two from drifting apart while you sleep.
Weight Considerations
Every mattress adds payload weight. A rough comparison at M1 platform dimensions (60" × 72" mid-size):
| Mattress type | Thickness | Approx. weight |
|---|---|---|
| Memory foam (2 lb/ft³) | 4" | ~15–18 lbs |
| Memory foam (2 lb/ft³) | 5" | ~19–23 lbs |
| Memory foam (3 lb/ft³, premium density) | 4" | ~22–27 lbs |
| Latex foam | 4" | ~28–35 lbs |
| Hybrid (spring + foam) | 8–10" | ~45–65 lbs |
A standard 4" foam upgrade adds roughly 15–18 lbs, a manageable payload cost. Jumping to a premium 6" latex adds 35+ lbs. Use the payload calculator to roll your mattress choice into your full build weight.