In baseball, hitting for the cycle is hitting a single, a double, a triple, and a home run, all in the same game. With my most recent purchase, I have hit for the “51” cycle. I now have at least one of every significant “51” variant made in Janesville. (I originally posted this entry in one of the fora I visit, but I’ve added a little more description and a picture or two here — not to add breadth in terms of the number of variants but to add depth by showing multiple examples of a couple of the variants.)

So here we go, roughly in chronological order.

First year, with Speedline filler. Blue Cedar, with Wedding Band cap (polished stainless steel with a gold-filled band). First-year pens were made only in the double-jewel version, with jewels on the cap crown and the barrel blind cap.

Wartime (WWII) and postwar production, with plastic filler. Blue Cedar, with lined sterling silver cap. Wartime production of double-jewel pens was cut drastically, but some were made. This is actually a 1946 pen.

Wartime and postwar production, with plastic filler. Burgundy (rare color), with Stacked Coin cap. After the beginning of the war, most “51”s were the single-jewel variant, without the blind-cap jewel and tassie. (Some collectors refer to these pens as “bullet bottom” pens.)

Red Band. Black, with semi-matte Lustraloy cap. The Red Band variant uses a spoon filler that is operated by a pushbutton similar in appearance and action to the Speedline Vacumatic filler (but requiring only a single stroke to fill the pen). For various reasons, the Red Band was unsuccessful, and Parker made it only in 1946 and 1947. Today it’s the rarest “51” variant.

Vacumatic-filling Demi. Cordovan Brown, with matte Lustraloy (stainless steel) cap. Parker made this shortened single-jewel variant for only one model year, in 1947.

Vacumatic-filling demonstrator. Transparent, with matte Lustraloy cap. Parker made demonstrators to show off the revolutionary engineering inside the “51”, but earlier ones had opaque black barrels, with only the shell (hood) made transparent. After all, the Vacumatic filler wasn’t what the company wanted to show off. But this 1948 pen is all transparent. I wonder why. Whatever the reason, I don’t consider this pen as a variant; it’s just a transparent example of the ordinary “51” of the time.

Aero-metric Demi. Teal, with matte Lustraloy cap. In 1948, Parker introduced its new Aero-metrtic squeeze-filling “51”. The Demi was the first of the Aero-metric pens to appear, and it was a complete redesign, shorter than the standard-size model and more slender to retain the aesthetics of the original. Gone was the dumpy Demi.

Aero-metric Standard. Plum, with parallel-line gold-filled cap. With its 4Q1948 transition to the Aero-metric filler, the standard-size “51” became officially the Standard.

Flighter. Brushed stainless steel barrel and cap. In the last quarter of 1949, the Flighter landed at Parker dealers. This iconic variant was modern, modern, modern, and it has also become a classic’s classic.

Cartridge/converter filler. Black, with matte Lustraloy cap. These pens were made for only a brief period around 1960. It was Parker’s attempt to extend its new filling system to the “51”, and it was a bust. (Among other things, it had a solid plastic block where the collector is in an ordinary “51”, and it doesn’t write nearly so werll.) Soon withdrawn, this variant, like the Red Band, is very uncommon.

Aero-metric demonstrator. Parker also made demonstrators of the Aero-metric “51”. This isn’t really a variant, so much as it is a special case of the Standard Aero-metric pen.

Mark III. Rage Red, with matte Lustraloy cap. Beginning with the Mark II, Parker transitioned away from the costly internal components of the Mark I (machined collector and feed, sterling silver breather tube), replacing them with plastic parts. The outside also changed, as with the Mark III the cap jewel disappeared.

I don't have a Mark II. But I do have one more significant variant. In this case, the significance is not in the pen, although this one is a Navy Gray Vac filler. The important thing here is the clip, which has no Blue Diamond. This clip, I believe (as does David Shepherd, author of the definitive book on the “51”), was made to go on pens produced for test marketing in Latin America before Parker introduced the “51” in the U.S.A.

And that, Gentle Reader, is my romp through the landscape of the Parker “51”.