Bolt Introduces Suspension System Into Tennis Rackets


When carbon fiber rackets reached the tennis world in the early 1990s, they were lightweight and stiff — good for performance but poor for shock absorption, leading to an uptick in arm injuries. At the time, a New York area tennis pro with a background in architecture and engineering, Brett Bothwell, began brainstorming solutions. The result was the ZipStrip, a suspension system embedded in the frame that he is marketing as Bolt rackets.

The ZipStrip, which is cataloged as U.S. Patent 6,971,964, purports to achieve what Bothwell calls the “fundamental conundrum of racket design” by enabling the coexistence of the properties enabled by a stiff frame (to generate power) and one that is flexible (to enhance command) that also absorbs shock and lessens the stress on a player’s arm.

“The suspension represents a means of controlling the ball and the action,” Bothwell said, saying that his invention helps the technology move in the direction of a “truly modern racket where it’s a dynamic, responsive instrument instead of a stick with strings.”

Bothwell had played tennis his whole life, earning a national junior ranking and captaining the squad at Illinois Institute of Technology. After graduation, he moved to New York City to work for renowned architect Philip Johnson while teaching tennis on the side, at the Roosevelt Island Racquet Club and West Side Tennis Club in Forest Hills.

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He approached sporting goods giant Wilson with his idea in 1996 and said he a “fairly serious discussion” about entering into a business arrangement with them. Though the deal ultimately fizzled, Wilson had given Bothwell a box of rackets into which he could install his invention for a demonstration. A self-described “tinkerer” since childhood, he manually cut open the carbon fiber rackets in his home, string and frames everywhere, reliant on architectural tools like a t-square and parallel ruler. Ultimately, he created working prototypes that he brought with him to tennis clubs.

Around the same time, however, Bothwell was introduced to Hall of Famer John McEnroe through a mutual friend (former NYC mayor David Dinkins, incidentally). McEnroe took a turn using the Bolt racket and, Bothwell said, liked them enough to make a referral to a German racket company. (An inquiry to McEnroe’s agent for comment had not been answered at press time.) That also did not result in a business partnership, but Bothwell said McEnroe’s support was important affirmation to pursue his product. Dinkins, for what it’s worth, has publicly endorsed the product, telling New York Tennis Magazine, “The Bolt racquet has added years to my game and allows me to play for a longer time frame each time.”

By 2006, Bothwell contracted a factory in China to start manufacturing his rackets, calling the actual production a “mere miracle” given his manual design process and coordination of specs via faxes and emails. More recently, he has partnered with Dassault Systèmes’ Solidworks for 3D CAD designs and printing. “Your vision of what becomes possible in the world becomes different,” he said of the new technology.

Bolt’s rackets have yet to be used by any professional tour players, but a network of teaching pros, especially in California and Florida, have become his word-of-mouth sales team for now. Bothwell said he hopes his racket design might “pressure the market enough to accept a new paradigm.” No longer would the racket act as a conductor transmitting force into a player’s arm, he believes, but instead work as a buffer between ball and body — all without sacrificing performance.

“We’re at the heart of the performance of the racket,” he said. “We’re getting a much bigger sweet spot. We’re getting longer dwell time, and we can begin to control the amount of time that the ball sits on the strings.”