Four flavors of the Eberhard Faber Mongol mechanical pencil No. 38, complete with pocket clips and clamp erasers.
Before the company began selling mechanical pencils, extenders with clamp erasers were paired with Van Dyke and Mongol pencils.
1923 Eberhard Faber Co. Catalog
The wood-cased versions of the Mongol pencil line far-outlived their mechanical cousins (the brand itself lasted for more than 80 years), but perhaps the No. 38 was in part an extension of the 1582’s design.