Flexsteel Blue Steel Spring Close-up

The Blue Steel Spring sits at the core of our upholstered furniture.

What’s inside matters

Before you buy a car, you probably pop the hood, take a peek, and ask a few questions even if you have no idea what you’re looking for.

When it comes to buying a couch you likely take a different approach—choose one that matches your style and provides a soft place to land after a long day. But what about everything you can’t see? Do you ask how it’s built, what it’s made of, or how you can be sure it will last?

Flexsteel furniture is made with integrity from the inside out. Every piece is designed with purpose and precision. In fact, if you flip over any of our couches or chairs you will see exactly what we’re talking about.

We’re committed to crafting furniture of the highest quality.

Engineered to Last a Lifetime

At the core of our upholstered seating is Flexsteel’s very own Blue Steel Spring. This patented component is not hidden behind a fabric dust cover. It is left in plain sight so customers can see the remarkable technology that powers our lifetime guarantee.

The all-riveted, high-carbon, steel banded system gives each one of our couches and chairs lasting strength and comfort. Over the years we have refined and perfected the original Blue Steel Spring to better suit the advancement in furniture construction and ensure the highest level of quality.

Today, we make four varieties of Blue Steel Springs, all right here in the USA at our plant in Dubuque, Iowa.  While built on the same scientific principles, each variety places extra support where needed most for the specific couch or chair in which it lives.

Innovative Design, Exceptional Durability

The Blue Steel Spring was invented in 1910 by Swiss engineer E.W. Schlappritzi. While studying the laws of flexibility at the University of Zurich, he conceived of a new and better performing spring for use in a variety of manufacturing categories. Schlappritzi experimented with materials and forms, tinkered and tweaked to determine the right combination for peak performance. The final product was an all steel spring with a unique helical shape that was—by all standards—superior to its predecessors.

The first commercial application of the spring was in European railway train car seats. Despite the daily impact of hurried passengers, the innovative new design gave seats exceptional durability and a longer life.

Schlappritzi went on to work in the United States, then returned home to serve as a Captain in the Swiss Army. In 1918, he came back to the U.S. where he formed the Sanitas Spring Corporation. While he saw some success making springs for beds, sofas, and chairs, his business did not flourish as he had hoped.

In 1925, nearly out of money and losing hope, Schlappritzi met Cliff Curtis and Herb Bertsch of the Grau-Curtis Company. Looking for a way to differentiate their upholstered furniture from the competition, they began using Schlappritzi’s unique spring in their furniture. The “bottomless spring” as they called it, proved such a distinctive selling point that in 1927 Grau-Curtis bought half of the Sanitas Spring Company later renaming it to Flexsteel Spring Corporation.


The C-Flex spring is featured in a variety of our 5000 series sofas.  And the "C" could easily stand for "comfort." Evenly spaced, dual steel ribbons run the length of the frame from the front to the back of the seating area, where each ribbon ends in a graceful, c-shaped arch, providing extra support you'll appreciate.

Blue Ribbon

The Blue-Ribbon unit has defined the heart of our company – and our name – from the very beginning. Similar to the C-Flex unit, it has a solid arch riveted to the back of each steel ribbon for additional support. And, for even more built-in durability, another ribbon solidly bands the entire system together.


The DualFlex Spring System offers the superior comfort and support so important to today's furniture shopper. Sturdy steel ribbons attached to super-flexible coils provide a wider range of motion, and once the entire system is bolted to the seat frame, it's ready to provide years of dependable service.

Technology That Works

More than one hundred years since its creation, the Blue Steel Spring continues to differentiate Flexsteel products.

The strength and resilience of the Blue Steel Spring creates a “just right” balance of softness and support as well as enduring construction. And, unlike traditional eight-way hand tied systems offered by other furniture makers, our upholstered seating never needs a tune-up or tweak.

So whether you’ve got big people or little people, wild jumpers or careless ploppers—not to worry—the Blue Steel Spring has got your back.

Flexsteel Furniture for Life

We stand behind our furniture because we have had over 100 years of experience to perfect it.

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