thier are numerous versions of the "handbook",, a large print edition,the tool box edition, a regular size edition,a pocket edition, a guide edition,and a dvd edition. most people have the tool box edition which fits in the center drawer of a kennedy toolbox,regardless which one you have i would get a popular one meaning their are plenty on e -bay fairly priced, so when you want another version you get the same edition ,25th, 14th, 29th etc..this is esecially critical if you get the Handbook Guide. the MH is full of good info but their is nothing in it to tell you HOW to use info,, the Guide book will do that with problems that can be solved with info in MH,, but you MUST get the Handbook Guide same edition as the MH, as it referrs to info on a certain page in the MH and the MH adds pages every edition,so a MH #25 and a guide book #29 wont work well together, you must match them up as to the same edition number,16, 25, 29 or what ever.