The Shoe Pouch was designed by Grantwood Technology, LLC to allow runners and walkers to use the Nike+iPod Sport Kit® with any type of shoe. When designing the Shoe Pouch, our primary goal was to ensure a snug fit, extensively testing it with reinforced, nylon lace loops, and a Velcro® closure over the insertion slit. These designs maximize the durability of the Shoe Pouch while, most importantly, maintaining the accuracy of the Nike+® system. The Shoe Pouch matches the correct longitudinal alignment of the sensor, completely covers the sensor and attaches through the laces for excellent security. With a small, low profile, secure, neoprene design, the Shoe Pouch is the answer to using the Nike+iPod® with any style of shoe. With over 20,000 sold, we have saved our customers well over a $2,000,000 in purchases of new Nike+® shoes. If for any reason you are not 100% satisfied we will guarantee a replacement of your purchase or a refund. We stand by the Shoe Pouch as our product and look forward to you becoming another happy customer. For US customers, we now offer expedited shipping via USPS Priority Mail (2-4 days after shipping) or you can chose standard shipping via USPS First Class mail.