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10 Best firm mattress kings of 2025
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Best Choice1
NectarNectar Classic 12” King Mattress - Medium Firm - Contouring Memory Foam - Cooling Top Layer - Support & Pressure-Relief - Mattress in a Box - 365-Night Trial & Forever Warranty
Key specs-
size:King
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construction:Foams and fabrics
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fill material:Memory foam
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dimensions:80 x 76 x 12 inches
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top style:Signature combination
9.7Exceptional
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Value for Money2
BedStoryBedStory Firm King Mattress 14 inch - Pain-Relieving Hybrid Mattress for Extra Lumbar & Hip Support - 365-Night Trial No Sagging Bed in a Box - No Odor, Fiberglass-Free, CertiPUR-US Certified
9.6Exceptional
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3
![ZINUS 12 Inch Green Tea Memory Foam Mattress [New Version], King, Fiberglass free, Medium Firm Feel, Zoned Pressure Relief, Certified Safe Foams & Fabric, Mattress in A Box](https://d1ttb1lnpo2lvz.cloudfront.net/7e0a079/loader.svg)
ZINUSZINUS 12 Inch Green Tea Memory Foam Mattress [New Version], King, Fiberglass free, Medium Firm Feel, Zoned Pressure Relief, Certified Safe Foams & Fabric, Mattress in A Box
Key specs-
size:King
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construction:Zoned pressure relief
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fill material:Memory Foam
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dimensions:80 x 76 x 12 inches
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top style:N/A
9.5Excellent
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4
BedStoryBedStory Firm King Mattress 12 Inch - 7-Zone Hybrid Mattress Extra Lumbar Support - Deep Sleep Pain Relief Contouring Bed in a Box - 365-Night Trial, Fiberglass-Free, CertiPUR-US Certified
40% Off9.4Excellent
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5
SLEEP100SLEEP100 King Mattress 12 Inch, 5-Zone Deep Sleep Firm Mattress with Extra Lumbar & Shoulder Support, Hotel Collection Hybrid Mattresses Pain Relief - Fiberglass Free & No Odor - 365 Night Trial
9.1Excellent
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6
AyeawoAyeawo Firm King Size Mattress, 12 Inch Hybrid King Bed Mattress with Gel Memory Foam and Pocket Springs, Comfort Bed in a Box, Pressure Relief and Motion Isolation, 365-Night Trial, CertiPUR-US
28% Off8.8Very Good
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7
KOULABR ZKOULABR Z King Size Mattress,14 Inch King Mattress in a Box,Superior Hybrid with Gel Memory Foam or Back & Lumbar Support,100 Night Trial,Maximum Support,Pressure Relief,Zoned Support Spring, Firm
23% Off8.6Very Good
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8
VIPNOW12 Inch King Size Mattress - 2025 Upgraded Hybrid Cooling Gel Memory Foam & Pocket Coils, Medium Firm Mattress in a Box for Back Neck Pain Relief, Motion Isolation, Edge Support, CertiPUR-US Certified
25% Off8.5Good
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9
COOL GELCool Gel Chill 14 Inch Medium Firm Memory Foam Mattress King Size, with 2 Bonus Cool Gel Memory Foam Bed Pillows, 14" with Pressure Relief, CertiPUR-US Certified, Cooling King Mattress in a Box
8.2Good
Our Rating
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10
RuoysunRuoysun 14 Inch King Size Mattress in a Box, Cooling& Breathable Firm Mattress with Gel Memory Foam and Pocket Springs for King Size Bed, Motion Isolation, 100 Night Sleep Trial, CertiPUR-US Certified
37% Off8.1Good
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