This vintage Texas Instruments SR-52 slide rule calculator program workbook from '76 includes a promotional flyer for the SR-52 and SR-56 calculators. The workbook is in excellent condition, providing a fascinating insight into the early days of computing. The SR-52 was one of the first programmable calculators, with a magnetic card reader that allowed users to store and recall programs. This item is a must-have for any vintage electronics enthusiast or collector. Both have water damage that doesn't impact legibility, see pics.