The early Sheaffer demonstrator pencil, with cutaways to show off how they work, appear at frame 2a on page 136 of The Catalogue:
Yeah, it's cool, but it's not nearly as cool as the one Gary Garner had in tow at the Raleigh show:
Same concept, but in an oversized Sheaffer "Titan" pencil! Notice how well crafted the cutout is in the barrel:
and there's even one in the tip:
and lastly, a third cutout on the back side of the barrel, near the top:
Unlike the other Sheaffer show-and-tellers, Gary had this one available for sale, priced according to its extreme rarity. Nice find, Gary!