This insert can be used in the coccyx and heel section of your mattress. It features 3” of Viva foam. Viva foam looks like individual foam segments, we refer to this engineered foam as our Multi-Directional (M.D.) technology. The M.D. technology allows for targeted immersion based on the users’ needs and positioning on the insert. As an added bonus, the M.D. technology provides a high level of friction and shear reduction being as each foam segment moves in conjunction with the user. The Viva insert also features an incontinent proof cover in either a friction fit option to fit in the coccyx region of the T-Fit mattress, or the Velcro fit cover to secure to the heel section of the T-Fit mattress.