Whilst browsing sleeping mats on-line, I came across (no pun intended) this description. I can only assume it's a mat designed for those on long trips, who'll be away from their home comforts for a while

Klymit Inertia XL Ultralight, Ultra Comfortable Sleeping mat/Pad
Like its nimble little brother the Inertia X Frame (IXF), this Inertia XL is the lightest, most compact and technically advanced camping pad in its category. The Inertia XL (IXL) offers increased support, body mapping, coverage area, tossing room, and even an integrated head cradle pillow.