Transform your sleep experience with a more targeted, supportive mattress from Serta. Layers of Deep Reaction™ and Cool Action™ Dual Effects® Memory Foams cover an individually wrapped coil innerspring. The Serta Masterpiece William Firm Eurotop California King Mattress is ideal for all sleep types, helping you wake up refreshed after a night of cool, comfortable sleep.

Two Types of Memory Foam for Ultimate Comfort

Serta's Masterpiece William Firm Eurotop Mattress features two types of memory foam for a more targeted, supportive surface. The Deep Reaction™ Memory Foam offers a substantial, deep-down feel that's unique to Serta. The Cool Action™ Dual Effects® Memory Foam provides cool-to-the-touch, superior comfort all through the night.

Coil Innerspring Delivers Comfort and Support

Get exceptional support from the Serta's layers of foam and individually wrapped coil innerspring for unparalleled comfort and less motion transfer. The individually wrapped coils move independently to reduce the sensation of movement, making it excellent for couples. And when your pet wants to sleep on the bed!

What kind of box spring is included with this mattress?

The Serta Masterpiece William Firm Eurotop California King Mattress includes your choice of either a standard 9" or low-profile 5.75" StabL-Base box spring. It is also compatible with adjustable bed frames.


Delivery, Set-up and Mattress Haul-awaySerta’s White Glove Delivery+ Service* includes in-home delivery, up to two flights of stairs. The delivery agent will remove the mattress from packaging and set-up basic bed frames (if no tools are required). The Member may ask the delivery agent to move a used mattress to another room at the location or haul-away the old mattress from the premises. Estimated delivery time is 10 to 12 business days for standard zones; remote zones may take longer. The delivery agent will call the Member to set up an appointment.


Mattress Buying GuideLooking for the perfect mattress for your needs? Click to view our Mattress Buying Guide.


Need Help? Ask our dedicated Sam’s Club members-only Serta hotline, staffed especially for you by Serta Mattress Specialists: 1-888-240-1945 available 24 hours/7 days a week.

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