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KLM's Correction Techniques

Hand Corrected

Hand Corrected is the traditional way of making foot orthotics. The negative casts are corrected and converted into a positive mold. Per the prescription, accommodations are added to the mold. An orthotic is pressed to the mold to create a custom handmade device.


System_Rx is a computerized cast correction system. The critical data is taken from the negative casts and entered into the system. Per the prescription, corrections and accommodations are added to the data. The computer generates a positive mold to which a custom orthotic is pressed. By using System_Rx you eliminate the labor expense of pouring and correcting the casts by hand. System_Rx technology was originally developed between 1990 and 1999. The technology was the result of KLM technicians programming computers and milling machines to make custom prescription foot orthotics. After mathematically analyzing thousands of uncorrected and corrected plaster models of men’s and women’s feet, KLM technicians began to recognize and identify common shapes and structures that resulted from creating plaster foot models and then correcting them to meet the specific needs of individual patients. After a decade of research and development, System_Rx technology proved to be more accurate than traditional methods and as well as more cost effective—revolutionizing the custom foot orthotic industry. And System_Rx technology is only available from KLM Labs, Inc.—the leader in fabrication and design of custom prescription foot orthotics and ankle foot orthotics.


Value_Rx was developed by monitoring System_Rx and realizing that 99 different shapes were used more than 70% of the time. These 99 shapes are now injection molded as polypropylene shells available in four rigidities. When KLM receives casts from a practitioner, the critical data is taken from the negative casts in the same way as in the System_Rx technique. However, instead of hand pressing an orthotic to a positive mold, the computer system selects the correct injection molded System_Rx Shell for the patient. Extrinsic posting, top covers, and forefoot accommodations can then be added to the device. Value_Rx is designed for patients with normal foot types and is not recommended for patients with severe deformities.

California Preforms

The California Preform is a shape defined as the "Average custom foot orthotic by shoe size." This shaped was developed as an extension of KLM's System_Rx technology, and is essentially the most common orthotic shape that is manufactured. KLM Labs designed the CP-3300 molds using this shape, so you can order cost effective, injection molded orthotics by shoe size. For the benefit of practitioners and patients alike, all of KLM’s Rx Foot Orthotics can be also made by shoe size, as "California Preforms". Yes, that means all of the Sport, Fashion, Geriatric, Pediatric and Diabetic custom orthotics. If, for whatever reason, casts of the patient’s feet are not available, or, as a cost effective alternative to custom orthotics, simply check the box labeled “California Preform” in the upper right hand corner of KLM’s Rx form and include the patient’s shoe size. Also, enjoy the California Preform discount! Questions? Don’t hesitate to contact our world class customer service team by email at or by phone at 800-556-3668.