No mechanical engineer can go through life without using some of the formulas or information on some issue related to the design of mechanical machinery (or hydraulic or electrical). Within the thousands of pages is everything from mathematics to strength of materials to bolted fasteners to riveting to hydraulic power to electric wiring. This is a handbook that always gets used by engineers on projects whether big or small. I recommend the large print. I have the smaller sized 23rd edition, and as I aged, I found it necessary to read the print with a magnifier. (That is what happens after age 40.) The large print version is not really large print, it is what we would call normal sized print that we would read every day. Size-wise the book is comparable to the old family Bible passed down through many generations. I have been an engineer for all my life and Machinery's Handbook is my prime source of engineering information.