The Schick Injector single-edged razor
A Short History of the InjectorJacob Schick (aka Col. Schick) served in the US Army (1898-1910, 1916-1918) and actually achieved the rank of Lieutenant Colonel. It was in the Army that Schick was exposed to the repeating rifle and its ability to load multiple cartridges via a magazine or a clip. After returning home, Schick, inspired by the repeating rifle, designed a razor with which the user would not have to touch the blades to change ("reload") them.
Col. Schick invented the repeating razor, which began manufacture by the Magazine Repeating Razor Company in 1926. In 1928, J. Schick sold his interest in the company and went on to design a (successful) dry shaver. In 1946, Eversharp bought the rights to the razor. Eversharp continued the injector line until it was bought by the Warner-Lambert Company in 1969. Injectors were strongly popular in Japan, much more so than Gillette products (after a Gillette blunder), from the 1960s onward,  topping even the Japanese company Feather, whose DE blades remain popular.
ModelsThis is, by no means, a list with comprehensive descriptions or values. The articles cited have far more detailed information.
Repeating RazorsThe repeating razor was the forerunner of the injector that we now know. It held the blades in the handle and had an interesting reloading mechanism. To change the blade, one would turn the shaving head (so it aligned with the handle) and cycle the base of the handle (a small "knob") back and forth.
Type A (1926-1927): Cylindrical body with folding head.
Type B (1927-1932): Rectangular body with folding head.
Type C (1933-1941): Rectangular body with new shaving head, and loading, design. All models came packaged in a narrow white box with blue trim.
- B1 - Silver plate body, no cap. Packaged with white box and leather sheath.
- B2 - Gold plate body, no cap. Packaged with clam shell case.
- B3 - Sterling silver body, with cap. Packaged with clam shell case.
- C1 - Open comb
- C2 - Closed comb
- C3 - Bar guard
Early InjectorsThe early injectors are the beginnings of how we know the injector today. The blades were held separate from the razor itself. But, the idea of being able to change blades without touching them remained. The changes through these, to my eye, appear to be subtle.
- Type D (1935-1935): Movable spring.
- Type E (1935-1945): Caramel Bakelite handle.
- Type F (1940-1941): An alloy model that resembles more modern injectors, rather than its contemporaries.
- Type G (1946-1955): Various finishes with plastic handles in different colors.
- Type H (1946-1955): A women's razor. Compact, flat, and designed for travel.
Modern InjectorsThe injector as we know it today. The traditional design was changed. The head became more molded, and lost the circular rivet from the early injectors. The details become even more subtle. Because of this, and the risk of pure plagiarism it entails, details of each particular model can be found on the pages cited for this section.
Injector-style blades can be found in most pharmacies, online retailers, and other sources. The injector blade is, to be repetitive, an injector. Unlike other blades, the "case" is an integral part of the blade. The case has a "key" which allows the blade to be inserted.
The KeyThe key is not an actual key like you would find to a lock. It is a simple wedge that inserts between the head and spring. This releases tension on the blade, and allows for the old blade to be pushed out. The key also aligns the case with the razor, so that the new blade can push out the old blade. As you can see, the key is an integral part of the design.
Schick bladesCurrently made in China, Schick blades can still be found in many sources. The blades are good quality, and the keys will almost always align perfectly providing for ease of use.
Aftermarket bladesThere are several makers of injector blades, such as Personna, Ted Pella (distributor), and generic brands. Other manufacturers' blades may have problems with alignment. This is not to say that the blades themselves are not of good quality. Quality is often a matter of personal opinion, and so that will be left for discussion elsewhere. It appears that plastic bodied cases may have a greater problem with alignment that metal bodied cases. One of the solutions that some have advocated is to load blades into a metal bodied case, thus maintaining the critical key-alignment.