Mattress Online Rock Hard Mega Firm 1500 Pocket Mattress
The Rock Hard Mega Firm 1500 Pocket Mattress does exactly what the name suggests.
- Extra-firm for back & front sleepers
- Handcrafted in the UK, fully recyclable
- 100-night trial & 5-year guarantee
£258
Get the lowest price we've found
Mattress Online describes the Rock Hard Mega Firm 1500 as extra firm, and it's built for sleepers who want a properly solid surface rather than a gentle one. Inside you'll find 1500 pocket springs, which means each spring moves independently to contour around your body, topped with soft white fibre fillings for a touch of cushioning. At 25cm deep with a viscose fabric cover and steel piping edge support, it's a straightforward, no-frills build. It comes in six sizes from small single to super king, with a 100-night trial and a 5-year guarantee.
Mattress specifications
Firmness
Firm
Type
Pocket Spring
Depth (cm)
25
Number of Layers
2
Trial Period (nights)
100
Warranty (years)
5
Price Range
£258 to £474
Best Sleeping Position(s)
Back Sleeping
Stomach Sleeping
Certifications
BS 7177
Assessed from Mattress Online's published specification for this mattress, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
If you sleep on your back or front and find most mattresses too soft, this is the sort of extra-firm support worth a look. The 1500 pocket springs respond to your body individually, which means firmer pushback where you're heavier and less pressure elsewhere, while steel piping around the edge helps the sides hold their shape. It's handcrafted in the UK, from a National Bed Federation approved brand, and fully recyclable at the end of its life. The 100-night trial matters here: extra-firm mattresses divide opinion, and being able to try it at home takes most of the risk out. Free delivery to most locations, with next day available on weekdays, is a genuine convenience too.
Key features & layer details
Comfort Layer
Soft white fibre fillings, finely filled with high density compressed polyester. This gives a thin layer of cushioning over the springs, which means you'll feel comfort at the surface but firmness underneath rather than a plush, sink-in feel.
Support System
1500 pocket springs that gently contour around your body for personalised support. Because each spring moves independently, you get support matched to your shape and less motion transfer if you share the bed.
Layer details from mattressonline.co.uk product page, September 2026.
Best suited for?
Back sleepers
The extra-firm surface and 1500 pocket springs give solid, even support, which suits anyone who finds most mattresses too soft when lying on their back.
Front sleepers
A thin fibre comfort layer over the springs keeps the surface firm underneath you, so you feel held up rather than sinking in.
Couples
Each of the 1500 pocket springs moves independently, which means less motion transfer when one of you turns over or gets out of bed.
Eco-conscious buyers
Handcrafted in the UK and fully recyclable at the end of its life, this mattress is a sensible pick if end-of-life disposal matters to you.
Side sleepers, particularly lightweight ones, will likely find this too firm at the shoulder and hip. Anyone who enjoys a soft, cushioned or hugging feel should look elsewhere. This is an extra-firm mattress by design, and there's no thick comfort layer to soften the springs beneath you.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Mattress Online Rock Hard Mega Firm 1500 Pocket Mattress
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FAQ's
How firm is the Rock Hard Mega Firm 1500 mattress?
Mattress Online rates it as extra firm. Owner reviews back this up, consistently describing a substantially firm surface with minimal dipping. It suits back and front sleepers who want solid support, although side sleepers may find it too unyielding at pressure points.
Does the Rock Hard Mega Firm mattress come with a trial?
Yes, Mattress Online offers a 100-night trial, so you can sleep on it at home before committing. That's a sensible safeguard with an extra-firm mattress, as firmness this pronounced isn't for everyone. There's also a 5-year guarantee covering manufacturing faults.
What sizes does the Rock Hard Mega Firm 1500 come in?
Six UK sizes: small single, single, small double, double, king and super king.
How deep is the Rock Hard Mega Firm 1500 mattress?
It's 25cm deep, which is a fairly standard depth that most fitted sheets will accommodate. Inside that depth sit 1500 pocket springs topped with soft white fibre and compressed polyester fillings, finished with a viscose fabric cover.
Does Mattress Online deliver the Rock Hard Mega Firm mattress for free?
Delivery is free to most locations, with next day delivery available on weekdays and weekend delivery also offered. Delivery to your room of choice and old mattress removal are available for an extra charge.
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