stick on tide charts?

just saw these in a sea kayaker mag…

any one tried them???seems you have to get a enw on eevery year…intriguing thought-but would like input if there is any…

stickontidecharts.com

Read the Website
and it sounds interesting but I don’t think I’ll run out and get one. However, you don’t have to buy a new one every year. If you into the “meat” of the website you’ll find a page that talks to making adjustments to chart for a couple of years downline.



SYOW

Hmmm…
I just read through their whole site… but I can’t figure out exactly what they are selling. There isn’t even a picture of the product? Is this just a sticker with info that helps you determine the tide times at your location?