Yea roger that. Work great so long as you have a right in the rain pin. I will say this though. Purchase one and instead of having to purchase another one down the road, take a page from each section you want out of it eg. range card and laminate it with some acid tape or some sort of other laminant and purchase some "perminant super fine" map marker's and one alchohol marker and a rag for changes. The writing will not come off unless you remove it with some sort of cleaner like that. You can also get a little field book or small 8x5 pilot book or something equivalant with some sort of solid 3 ring binder system after 3 hole punching those pages and put them in that. You can also purchase those little tabs so you know which page is which for it which I think works much faster than trying to look for each page etc.
HTH brother!
Cheers,
RiP