The last slide rule K&E made, the Deci-Lon reflects a talent for going out in style. Those tapered endplates, the fancy triangle logo, the rakish stripes at the end of the slide... Who knew K&E had this repressed desire to be designing tailfins for Buicks? Like the 4181-1C this thing shows K&E's ability to make even plastic rules into something surprisingly solid.
These things go for just absurd gobs of money on EBay. I totally don't get that at all. It is a nice slide rule, it's true. But it's certainly not the fanciest one K&E made, nor the rarest. No accounting for taste, i guess.