Not the NEXT outdoor product, but something I have had for several years (Copyrght 1986) a book by Don Paul Titled "Everybody's Knife Bible". I bought mine in '89 or '90.

It's got some good tips and mods to your knife that will give you the time, height of objects and possibly even (My memory isn't positive), distance to objects.

AND it also has some survival tips. Mine is the 2nd edition. I don't think that everything in the book applies but if you can get it cheap enough it isn't a bad investment.