Sleeping on three inches of memory foam: cot, truck bed, tent, guest room

The 72-hour rule, the width problem, and what three inches of foam does and does not fix on a hard floor.

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This is a roll of memory foam three inches thick with a removable washable cover, straps and a bag. It is not an air mattress, it does not inflate, and there is nothing to puncture.

The 72-hour rule

We states that you should allow 72 hours for expansion. Take that literally. Unrolled foam recovers slowly, and the difference between hour six and hour seventy-two is the difference between a thin mat and the product you paid for.

Unroll it the day it arrives even if you need it next month. Judge it after three days, never before.

The width problem

Fit is the one aspect that runs against this pad: 13 positive against 15 negative, and the complaint is width rather than length. Cots and truck beds are narrower than people remember.

Mentioned above

3-inch memory foam camping pad, Grey

3-inch memory foam camping pad

Cot / 72*24*3 · Grey

  • 3 inches of memory foam, removable washable cover
  • allow 72 hours to expand

$49.99 recorded 2026-08-25

4.5★, 732 ratings, recorded 2026-08-25

Rated together with one other size or colour See it on Amazon
  1. Measure the usable width inside the rails of the cot, not the outside of the frame.
  2. Measure the length between anything that sticks up at either end.
  3. Compare with the size chart, and if you are between sizes take the narrower one.

What three inches does

It takes the edge off a hard floor and it insulates from below, which matters more in a tent or a vehicle than the softness does. Sleep quality runs 29 positive against 1 negative and quality 109 against 18, so it does the job it claims.

What it does not do is turn a plank into a mattress for a side sleeper who needs their hip to sink. Three inches of foam over a hard surface is three inches, and a heavy adult on their side will feel the floor eventually.

Washing and storage

The cover comes off and washes. Roll it with the straps rather than folding it into a corner, and give it the expansion time again after a long spell rolled up.

Camping and travel →The size chart →The 30-day proving ritual →

What buyers mention most, counted on 25 August 2026.