best spring mattress in 2024 growell beds and furnitures trichy Pocketed springs, also known as pocket coils or encased coils, are individually wrapped coil springs that are each encased in fabric. Unlike traditional innerspring mattresses where all the coils are interconnected, pocketed springs work independently of each other. This design allows the springs to respond individually to pressure and movement, providing targeted support to different areas of the body. It also helps to reduce motion transfer, making it an excellent choice for couples or light sleepers.