Leggett & Platt is the worldwide leader in developing and producing innerspring technology. Offering a unique blend of comfort and durability, innersprings are the most popular sleep core in the United States.

At Leggett & Platt, we produce a wide range of open coil and fabric-encased innerspring units including our popular family of ComfortCore® and our growing line of ActivEdge™ steel perimeter products.

Types of Innersprings

There are two major types of innersprings: open coil and fabric-encased coils.

Open Coil

To make open coil innersprings, wire is fed through a coiler where steel is shaped into springs. The strands of springs are moved into an assembler where helical lacing is threaded through key parts of the springs to connect the coils and form a cassette. An operator then moves the spring core to a clipping station where a Leggett & Platt partner adds clips, often connecting a border rod. Once the open coil innerspring unit is complete, it is flat-packed for shipping.

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To create ComfortCore® units, fabric is fed into the machine where the steel coils are inserted into partially formed pockets. Once a coil is placed inside, the pocket is ultrasonically welded and each spring is sealed inside an individual encasement. Coil strands are then fed into an assembler where a precision glue head applies adhesive to bond the strands together and form a full unit. Once the ComfortCore® unit is complete, it is roll-packed for shipping.

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