ViscoSoft 3-Inch Memory Foam Mattress Topper King - Reflex Cooling Gel Pad with Removable Washable Cover Review (2026)

What it is

This is ViscoSoft's 3-inch memory foam mattress topper in king size, part of the brand's Reflex Gel line, built from gel-infused memory foam and paired with a removable, machine-washable cover. The foam is CertiPUR-US certified, which means it has been independently tested for content such as heavy metals, formaldehyde, and certain flame retardants, and the fabric cover is OEKO-TEX certified for similar chemical safety testing. A 3-inch profile sits in the middle of the topper market: thick enough to noticeably change the feel of a firm or aging mattress, but not so thick that it becomes hard to fit sheets over or shifts the overall feel of your bed the way a very thick topper can.

Comfort and support

The gel-infused memory foam is designed to contour closely to the body, spreading weight across shoulders and hips rather than concentrating pressure at a few points, which is the main reason people add a topper like this over a firm mattress. ViscoSoft describes the foam as engineered to relieve back and hip pain, consistent with how memory foam generally performs by slowly molding to the sleeper's shape and then recovering once weight is removed. Because it is a single topper layer rather than a full mattress, it works best as an add-on to soften a mattress that has gone firm or lost its original comfort layer, rather than as a fix for a mattress with real structural sagging or support problems underneath it.

Cooling performance

The gel infusion in this topper is meant to offset one of memory foam's known weaknesses: its tendency to trap body heat because of its dense, slow-recovering cell structure. Gel particles or gel swirls mixed into the foam are designed to help pull heat away from the surface and spread it more evenly through the material, which can make the topper sleep somewhat cooler than a plain memory foam pad of the same thickness. That said, gel infusion is a moderate cooling measure rather than an active cooling system, and dense memory foam will still generally run warmer than latex, wool, or a thin fiber-fill topper. Hot sleepers who are highly heat sensitive may still notice warmth build up over a full night, especially under heavier bedding.

Care and cover

The topper ships with a removable, machine-washable cover that is meant to be taken off for cleaning without having to wash the foam block itself, since memory foam should never go in a washing machine or dryer. This is a practical feature for keeping the topper fresh over time, particularly for households with pets, allergies, or younger children in the bed. As with most memory foam products, the topper may carry a mild off-gassing smell when first unboxed, which is common with CertiPUR-US certified foam and typically fades within a day or two of airing out in a ventilated room before use. Straps or an anchor band on the cover help keep the topper from sliding around on the mattress underneath it.

Who should buy it

This topper suits king bed owners with a mattress that has become too firm or has lost its original softness, especially side and back sleepers who want more pressure relief at the shoulders and hips. It also fits anyone who prefers memory foam's slow, contouring feel over the quicker bounce of latex or hybrid toppers. It is a weaker match for sleepers who run hot and are sensitive to any warmth, since gel infusion helps but does not fully solve memory foam's heat retention, and for anyone who wants a topper light enough to move easily, since a full king size 3-inch foam block is bulky and requires a deep-pocket fitted sheet to cover properly.

Frequently asked questions