Pocket Coils  

Pocket or pocketed coils, also known as Marshall coils or encased coils, are wrapped in cloth, and connected to neighboring coils by strands of fabric attached with hot glue; no helicals or additional wire attachments are used.

Compared to other innerspring configurations, pocket coils enhance the mattress’s contouring effects and cut down on motion transfer. Not surprisingly, these mattresses tend to be the most expensive models available. However, many pocket coils are made of thin, non-tempered steel, giving these mattresses a shorter lifespan than other innersprings.