Welcome to Screwdriver 69's Chrome Cap Challenge. Collect all all 68 marked on the Geo-Grid to locate the coords to the 69th one. You will also need to find a random 4 in the 68 with padlock combos. The combos are in order based on the the cache number, but without all 4, you can not enter the 69th cache.
Check out my 5min video on YouTube for more details and information about the Chrome Cap Challenge. http://youtu.be/t0MNe9hQRYU