After the great success of cartridge filler Pelikano for children, Pelikan decided to produce cartridge filler pen for adults. In July, 1961, models P25/P15 were introduced. In the same year, the matching ballpoint pens R25/R15 and the matching mechanical pencils D25/D15 were launched (Pelikan Schreibgeräte). Befitting adult fountain pens, P25/P15 had a hooded gold nib, and P25 had a rolled gold cap, while P15 had a Silvexa (nickel silver) cap. Like Pelikano, cap safety device was not incorporated. Thus, except for the materials of nib and cap tube, P25/P15 were identical to that of Pelikano. Considering their structure and appearance, models P25/15 were virtually higher-end models of Pelikano, but they were positioned in the catalog as lower-end models of P1 (Pelikan catalog 110B (1963))⁽¹⁾. The initial color scheme was exclusively "sapphire blue", which was an attempt to promote a new fountain pen "brand color", just as Pelikan's earlier fountain pen brand color was green. This attempt, however, failed. At the request of the market, in October, 1961, Pelikan introduced the two models in black, too (Pelikan-collectibles). At some time point, the nib was modified. The new nib had slightly longer tines, and the visible area of the nib out of the section was increased slightly. Thus, P25/P15 were introduced with a fair amount of Pelikan's expectations, but they did not seem to be as successful as Pelikano.

At the end of 1964, Pelikano underwent a fundamental revision (model 2). The nib became larger, more elastic, and semi-hooded. The sections was equipped with an ink window. The cap became friction-fit. Accordingly, the design and construction of adult fountain pens were modified similarly in 1965. In the same year, P25/P15 was discontinued, and Pelikan introduced P30 with a rolled gold cap and P12/P20 with a Silvexa cap for the cartridge fountain pens.

Note:⁽¹⁾in the catalog, the prices of P1 RG, 400NN, P25, and Pelikano were 38 DM, 25 DM, 23.5 DM, and 6.9 DM, respectively.
⁽²⁾Probably, "R" stood for "Roller" (at first, Pelikan called ballpoint pen "Roller"), and "D" for "Druchstift (mechanical pencil)" (Pelikan Schreibgeräte). Thus, in 1961, "P" probably meant "Patronen (cartridge) Füllhalter" rather than Pelikan.