This Lutz No. 151P is a model I don't see often on slide rule sites. A full 25 scales, including the "Pythagorean" or P scale. And some of the scales are also extended on either end, which is handy.
The body is of bamboo, overlaid with a white plastic laminate. Bamboo wears well, and it still slides just perfectly. I found this slide rule, together with its pigskin case, in a St. Vincent's for only five bucks. Right alongside it was the K+E 4081-3 with its leather case-- also five bucks. Two fantastic log-log slide rules for next to nothing-- to this day, my greatest slide rule "find"!