A Brannock device is a used to measure the length and width of the foot in order to ensure proper shoe fit. It comes in green, purple, red or black. Now there are different models for men, women children and sports shoes. The device has two knobs for adjusting the fit cups at both ends for the curve of the heel, and a sliding bar for adjusting to the width of the foot.
Charles Brannock designed the device in 1927. Charles was born into the shoe business. His father, along with Ernest Parks, founded the downtown Park-Brannock Shoe Co. in Syracuse, New York in 1906. As a Syracuse University student, young Brannock wanted to find the best way to measure the foot. He played around with the idea for a couple of years and finally built a prototype using an Erector set. In 1926 and 1927, Brannock patented the device and created a company to build it: The Brannock Device Co., Inc.
Before the Brannock Device, a primitive block of measured wood was used to measure the foot. Of course, this method was not very accurate. The Brannock Device improved accuracy to being 95-96% right. (source: www.brannock.com)
This device put the Park-Brannock Shoe Co. way above its competition, because they could fit a shoe like no other store. Soon, though, the world got word of the new invention, and demand rose, so Brannock decided to expand his manufacturing facilities.
I found this fact particularly intriguing: During World War II, The Army hired Brannock to fit the enlisted men.
Charles Brannock died in 1993 at the age of 89. Sal Leonardi purchased the company later that decade. The Brannock Device is still the standard for the footwear industry today. However, some changes have been made and the company is now producing customized models and is considering producing a digital model.