How contour pillows are specified, and what the numbers mean

Density, certification, loft and cover material are the four things printed on an ergonomic pillow's spec sheet. Here is what each one refers to, using the published figures for one model.

Contour, not just shape

A contour pillow is moulded rather than stuffed. Instead of a rectangle that compresses wherever weight lands, it is cut with fixed high and low areas — typically a raised edge for the neck and a lower centre for the back of the head.

The point of the shape is geometry, not softness. Whether a given contour suits a given person depends on shoulder width, mattress firmness and preferred sleeping position, which is why the same pillow can feel right to one person and wrong to the next.

What CertiPUR-US® actually certifies

It is a certification programme for flexible polyurethane foam. It tests what the foam is made without and what it emits — restricted substances, formaldehyde and volatile organic compound levels — plus durability and performance criteria.

The published specification

Derila lists the Ergo model as follows:

• Dimensions — 21.3 in × 14.2 in × 4.7 in
• Weight — 36.9 oz
• Core material — 100% polyurethane memory foam, CertiPUR-US® certified
• Cover — included, described by the maker as breathable and hypoallergenic
• Design — five-zone butterfly contour

Care instructions from the manufacturer: the memory foam core is not washable and should be spot cleaned. The cover is removable.

Price, shipping and returns

The Ergo is listed at USD 133.30 on the company's own store, with free shipping within the United States and a 30-day return window stated on the product page.

One thing a pillow is not

Persistent neck pain, numbness in the arms or hands, or pain that wakes you are reasons to see a clinician. A pillow is bedding. The manufacturer says as much in its own disclaimer, reproduced below.