The 65 was E.S. Perry’s first fountain pen. I suspect the number was meaningful, but I can find no references to exactly what that meaning was. The pen is similar in nature to the Esterbrook J pens, a lever-filling pen with interchangible points. Where this pen differs from the Esterbrook is that it appears to aim more directly as a youth market, with none of the tipped high-grade point options offered by the American company. The also appear to have wanted to increase demand for calligraphy supplies, as Osmiroid offered a very wide range of italic points, including ones shaped to theoretically allow left-handed people into the game. For more on the point units, have a look down this link.
There are two different body patterns for the Osmiroid 65. The first is a fairly standard torpedo-shape, common to many pens. The second is an update, which I assume without assertion was done to coincide with the release of the 75. The pen is more angular in general, and has an asymmetrical hood around its cap jewel with suggests the headlight and fender of a late ’50’s GM sedan of some sort.
Production Run: Early pattern c. 1950 – c. 1965 (the latter date is essentially guess-work), later pattern to c. 1980.
Cost When New: An informant reports a leaflet from the 1970s giving the price for the newer pattern as $3.95, with points going at $1.40 (for modern value, try this calculator) Pricing on the early pattern remains obscure, and I remain interested in hearing from anyone who can fill in this blank.
Size: Early pattern, 13.2 cm long capped, 13.7 cm to the face of the section posted (as the points are of various sizes), 10.0 cm uncapped; later pattern 13.2cm long capped, 14.2 cm to the face of the section posted, 10.6 cm uncapped.
Point: Plated steel.
Filler: Lever, approx. capacity 0.8 ml. Cartridge-filling versions also exist, using a proprietary cartridge of about 1 ml capacity.
If you are relying on the preceding information to win a bet or impress a teacher, you should read the site’s scholarly caveat. Remember, this is the internet, and it’s full of bad information.