View-Master Model A Viewer - vintage - standard lens - 3rd version

,View-Master® Model A Viewer - vintage - standard lens - poor advance Composite Plastic (Tenite) was used in the manufacture; this is the third issue viewer. The  third generation viewers were sold found in  sturdy two piece boxes. All standard lens Model A viewers have minor to severe warpage, which was typical due to the tent used. It closes but often does not advance a reel cleanly through. The lenses are smaller than the previous viewers Model A viewers, which are known as LARGE LENS. NOTE: All Model A viewers warped shortly after production. All subsequent versions unsuccessfully attempted to resolve this issue, which was only resolved with the introduction of the Model B.  For information about TENITE (source for viewer manufacture, refer to the WIKIPEDIA article  https://en.wikipedia.org/wiki/Tenite Each version of the Model A viewers are offered by 3Dstereo in one of two conditions: common - warped and reel will NOT advance by pulling advance lever, thus requiring some assistance from ones finger to move it along seldom - warped but reel will advance by pulling advance lever Look for advance info in product description:: "Good Advance" or "Poor Advance" Small Lens Model A 1940-1944 3rd version viewer poor advance