About Tester

Custom Orthotics. The Same Custom Foot Supports We’ve Supplied Podiatrists Since 1932

Family Owned Since 1932

Born in Nebraska, of German parents, company founder Joseph Daniel Zinke was destined to learn at a tender age that a shoemaker’s son in the 80’s was required to forget play and grow up in the shoemaking business. At the age of 6 therefore he started his kindergarten apprenticeship. For years, his duty was to sit at attention before and after school in his father’s shop receiving daily instruction on the craftsmanship of transforming leather into custom shoes. At 14, Zinke left home to see the world and learn, to travel and earn .. then “my own shop” someday. It is from this commitment to footwear that Corefit Orthotics was born.


The period from age 10 to 14 saw him sweeping shop, saving scrap, salvaging nails, fetching, carrying, and actually shoemaking, bit by bit, slowly, thoroughly, with a meaning to each development. The first pair of shoes he made for his elder sister all by his own boyish hands, while not perfect, were a great personal success. They earned him his spurs, paved the way for shoes for the entire family including the teacher-father (a crowning triumph). A chair set on top of a flimsy fruit box, a brush, some polish and boyish smile “Shine, please mister, for a nickel?”  The first customer, a heavy man, brought catastrophe: a box broke, a chair fell and the customer with a bumped head berated the boy’s father. Joseph, scared stiff, dashed around the corner. He was temporarily out of business in 5 minutes.  Back into the shop to learn and grow.  This early training proved a wonderful background upon which further knowledge, achievement and ultimately our parent company, California Leather Jobbing, were built.

Comparison of shops and methods

After leaving home at the age of 14 to earn, travel and learn, his first job brought more experience and confidence. With it came a thirst for knowledge and adventure. Each new shop he worked for was carefully chosen and could be a “book” to read, digest, for future use. Shoemakers traveled in those days like wandering minstrels. It was the accepted thing.  Working from shop to shop, then from town to town, three weeks here, two months there, each new shop owner, his standards and methods, was an interesting study.  a newcomer look at the boss’s work, equal his standard, or leave! A life maxim “Observe, Remember, Then Compare” assisted young Zinke to develop a second interest: that of reviewing previous associations of shops and men. It was interesting to see that even after two or three years some shops had made marvelous advancement while others had deteriorated through either carelessness or lack of vision for the future.  Having worked for very careless employers and extremely critical ones__all experiences had a value.  They showed him what type of business proved most successful. It naturally served him later in establishing business methods, policies, standards of shoe service and the beginnings of the Corefit Orthotics brand.


The ethos behind the Corefit Orthotics brand remains unchanged since our first pair of self moldable “Zinke’s Foot Form Supports” was handcrafted in 1932: produce an affordable, self moldable custom shoe insert which helps relieve foot ailments which include plantar fasciitis, arch and heel spur pain. Zinke crafted custom made shoes the way they were made in his native Germany…”with contoured insoles, formed to fit the foot.” Unlike factory-made shoes, which had flat insoles, his custom made shoes left one feeling as though they were walking “on soft earth” instead of pavement. Zinke then thought, “Why not create an individual customizable insert that can be inserted into a standard type shoe, giving its wearer the comfort that is only derived from expensive custom-made shoes?”

A group of specialists was commissioned to developed a perfect, custom moldable insole which also turned out to be a revolutionary foot support. Notice we didn’t say simply an “arch support”…because it was actually a complete foot support.

It both stabilized and supported the weight bearing areas of the foot…both cradling the heel and supporting the longitudinal and metatarsal arches; providing solid comfort and relieving the pain associated with many foot disorders. The end result, coined the “Miracle Device” was thus born. A custom moldable device which when inserted into the shoe turns into a superior foot support, doing the job far better than most podiatrist molded orthotics that sell for $300 and upward. Up to now, our product has been sold exclusively to podiatrists, medical professionals and the US Military. While we are at the forefront of developments in foot orthotics, many tasks are best done by hand. As a family owned company, we’re able to nurture and preserve the traditional and complex hand-finishing skills that make our self moldable orthotics so unique. These self-imposed standards culminate in our flagship product: Corefit Custom Moldable Shoe Inserts.