I wanted to test the Adapto’s adaptobility and so shoved a 3 mm lead into the one above.  It works.  Later model 5616s will not take a 3 mm lead.

According to a timeline published in the 1976 Koh-I-Noor Rapidograph, Inc. catalog, the “Adapto-Clutch” was introduced in 1952.  I find it strange that it took until 1955 to file a patent claim.  Very early versions of the 5616 had “Italy * G3 * pat. pend.” stamped into the end of the pushbutton.  Most have “Italy” imprinted on the barrel.  Until about 1985 the nosepiece, collet, and pushbutton were gold plated.  Later models had nickel plated fittings.

reverse

reverse

This example has the pinkish grip of the earlier gold plated model, but the chrome plated fittings of the later models.

 

Note:  The sickly color is not an artifact of reproduction, it really is a duller yellow than previous models.

This is the most recent incarnation of the 5616. This version has an octagonal barrel, whereas the earlier models above have hexagonal barrels. Below is its packaging which pictures the earlier style.

Note the “DI” at the end of the barrel. The 1980 Koh-I-Noor catalog identifies this pencil as a 5616 D1.  The correct model is 5616 DI (uppcase i). reverse