This is a "Realpoint," which was an Autopoint brand (the name is a combination of Realite and Autopoint, the two companies which merged to form the Autopoint Products Company). According to Jim Stauffer, Realpoint was the brand Autopoint used to test market new ideas, which explains why this one lacks the familiar removable nose cone seen on Realites and Autopoints. The mechanism is a conventional nose drive.
Also, rather than being made of bakelite, another Autopoint standby, Realpoints are made in very attractive colors. Here it is, posed with the three examples pictured on page 23 of The Catalogue . . .
NOTE: This article is now included in the print version of The Leadhead's Pencil Blog, available anywhere you buy books, or also from The Legendary Lead Company.
To order, here's the link: Volume 1 at Legendary Lead Company