The Sheaffer Pen Company had it's beginning with a simple enough idea, the use of a lever to compress the ink sac inside a pen. With a patent issued in 1912, Walter A. Sheaffer left the jewelry business, and entered the pen making business. From Fort Madison, Iowa, the Sheaffer company began distributing hard rubber pens, in several sizes. These early pens proved to be quite successful, and it wasn't long before the company was on a solid footing, and was able to expand it's production facilities. Despite some early battles over copyrights to the design features of the lever filling mechanism, the most famous example of which resulted in the short lived production of Kraker brand pens, by a former partner of Sheaffer's, George Kraker, the Sheaffer pen company soon became one of the "giants" among American penmakers, easily rivaling Waterman and Parker.

In 1924, Sheaffer developed a new celluloid material for the manufacture of pen caps and barrels. Their name for the material was Radite, and the first pens were offered in Jade green and Black in that year, followed by Black and Pearl marble. The new material was used on the Lifetime pens, a pen which had a lifetime guarantee, signified by the White Dot, which soon became a Sheaffer trademark. Like the hard rubber pens which preceded them, the new celluloid versions were made in several sizes, from oversize, to ringtops. Production of hard rubber pens continued for a short while, as remaining stocks of material were used up.

In 1929, Sheaffer launched the Balance, perhaps the most important pen, form a design standpoint, of that time period. This pen introduced a new, streamlined look, it was promoted as "balancing perfectly in the hand". New colors were added to the line as well, Marine Green Pearl and Red Vein Gray Marble, and even a black with inlayed abalone chips. In 1936, a new look was introduced in the Balance line, with the arrival of the striped celluloid in Green, Brown, Gray, and Red. Also introduced was a new filling system to compete with Parker's Vacumatic. The Sheaffer plunger-vac system allowed the entire barrel of the pen to hold ink, resulting in a much higher ink capacity.

One Of Sheaffer's most interesting models from the 1940s was the Tuckaway. These diminutive pens were made specifically to "tuck away" in a pocket, with a very short length when capped, yet long enough to write with comfortably with the cap posted. The first version was a gold filled model using the lever fill mechanism and a conventional style open nib, this was shortly followed by models in the striped celluloid, using the plunger-vac filling system, which allowed them to hold a surprising amount of ink for such a small pen. These versions were fitted with the newer style Triumph nib, and could be had with caps in gold filled metal. The third generation of the Tuckaway pen was made of injection molded plastic, and were fitted with either the plunger-vac mechanism, or Sheaffer's new Touchdown mechanism. These versions could also be had with either the Triumph nib, or a conventional open style nib.

By the late 1940s, the shape of the Balance line had changed slightly, with a little more abrupt taper to the cap top and barrel end. Filling systems now included three different mechanisms, the traditional lever, the plunger-vac, or the new Touchdown, which used air pressure inside a sliding tube to compress a thin ink sac. Versions were offered in the striped celluloid (as lever fillers and plunger-vac fillers only) and later in several colors of the new injection molded plastic. Both Triumph style, and conventional open style nibs were offered.

The Snorkel, introduced in 1952 was Sheaffer's answer to the threat of the new ballpoint pens. Advertised as being the "clean filling" fountain pen, it was a large success for Sheaffer, and sustained them through the 1950s. The complex design used a thin tube which extended from beneath the nib to suck ink into the pen. The filler mechanism was similar to the Touchdown mechanism otherwise. These pens were thinner than previous models, in keeping with the trend of the times, and were offered in several combinations of color and trim, from all plastic versions, to solid gold.

The PFM, introduced in 1959 was Sheaffer's attempt to capture the top end writing instrument market. This pen was specifically designed to appeal to men (Pen For Men) and was offered in several versions: The PFM I which has a plastic cap and barrel, and a Palladium nib, The PFM II which has the plastic barrel and Palladium nib, and a brushed steel cap, the PFM III, with a plastic cap and barrel, and a 14K gold nib, the PFM IV, bright steel cap, plastic barrel, and 14K nib, and the PFM V, which has a plastic barrel, and a gold filled cap. The nib was a new inlaid style nib, it has since become a trademark design for Sheaffer.

In 1963 Sheaffer introduced the Imperial, in celebration of it's 50th anniversary. Looking much like a scaled down PFM, the Imperial also used the inlaid nib design. Early versions were made with the Touchdown filling mechanism, later ones were cartridge converter fill. The Imperial has been one of Sheaffer's most successful pens, in terms of the number made, and examples can be found in a number of colors of plastic, as well as gold fill, solid gold, and sterling silver.

The Targa was launched in 1976, and like the Imperial, became a very successful line for Sheaffer. Positioned as a step above the Imperial line, the Targa was offered in several finishes, from stainless steel to gold plate or sterling silver. In the UK and France, other finishes were offered, including several varieties of lacquer finish.

The Legacy, launched in 1995 is a remodel of the classic PFM, offered in several colors of lacquer over metal. This new pen is either a cartridge converter fill, or it can be used as a Touchdown style filler. In addition to the several finishes offered by Sheaffer, Classic Pens used the Legacy to make their CP4 series of pens in 1997, a pair of designs executed in guilloche engraved sterling silver.

In 1998, Sheaffer re introduced the Balance, with the Balance II. A cartridge converter filler, offered in four colors of acrylic, Crimson Glow, Jade Green, Cobalt Glow, and Amber Glow. In 1999, a special edition version was offered in a marbled blue, red , and brown color, called the Aspen, followed in 2000 by a blue and black marbled special edition called the Millennium.

Sheaffer has produced several Limited Edition fountain pens. The WA Sheaffer Commemorative was introduced to commemorate the founder of the company, Walter A. Sheaffer. The Balance LE was introduced in 1996, a classic interpretation of the Balance pens of the 1930s, it's an oversize lever filler in a red and gray marbled acrylic. 100 were made as clear demonstrator versions, and are highly sought after today.

Sheaffer has had a long standing working relationship with Levengers, a mail order company which specializes in reading and writing accessories. Using the Connaisseur, initially introduced in 1985 as a base, they created a series of translucent pens named after various oceans. The Levenger Seas series includes the Caribbean, Aegean, Adriatic, Red Sea, and Mediterranean.

As might be expected with a company as prolific as Sheaffer, their pens tend to get used in a lot of custom conversions. This pen was made from one of their No Nonsense Promotional ballpoints, with a vintage Triumph style nib fitted to an aerometric filler system.