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 premium winner | from ~$485 | Want a finished premium mattress but not the Hest tax. The one owners A/B against the Hest |
| 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 and a firmer feel owners prefer over the Hest's softer, "gelly" memory foam.
- 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.
One honest note up front: I take delivery of my own M1 on July 21, 2026 with the King Bed Extension. This guide is built from owner reports, manufacturer specs, and live pricing. Once I've slept in mine, I'll add a first-person verdict on what I actually chose and how it held up.
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.
Want to clone the Hest's feel? The Hest Dually is just two foam layers (a plush memory-foam top over a firmer support base) under a washable nylon cover, about 3.9" total. You can rebuild that exact stack: order a 3" HD36 support base plus a 1" memory-foam topper, then a water-resistant zippered cover cut to size. Prefer the firmer RoamRest feel instead? Run 4" HD36 straight and skip the topper. HEST markets its enhanced memory foam as staying soft in any temperature, but it publishes no test data, and the one in-depth independent cold test of HEST's foam (CleverHiker, 60+ nights down to -14°F) found it still firms up below about 10°F, like other memory foam. Read that as comfortable in mild cold, stiffer in deep winter. Either way, latex or HR foam don't cold-stiffen at all (the tradeoff is less memory-foam "hug"), so a custom winter build can match or beat the Hest on its own headline feature for far less. The Hest's drop-stitch base, separately, is a moisture barrier for soggy ground and rooftop tents that the M1's flat, dry, elevated platform doesn't need. Inside the M1, a custom foam stack with a waterproof cover matches what actually matters for a fraction of the price.
Step 1 — Order the foam, cut to size
Go to Foam Factory (foambymail.com) or a comparable supplier (Foamma, FoamOrder, or a local upholstery shop). 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. For a plusher top, add a 1" latex or memory-foam topper layer.
- 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. It keeps ~30.5" of headroom and ships compressed in a box, which makes it far easier to get into the camper than a finished mattress.
Expect roughly $80–$130 for a 4" cut and 7–14 business days to ship.
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.
| DIY component | Cost |
|---|---|
| 4" HD36 foam, cut to platform size | ~$80–$130 |
| Water-resistant zippered cover (custom cut) | ~$40–$80 |
| Second foam piece (king-extension owners only) | ~$40–$70 |
| Typical all-in total | ~$120–$210 |
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.