The challenge is on and Purex is inviting you to take part in a scavenger hunt. To participate in the Purex Scavenger Hunt you will need to find the small image hidden on the Purex website for a chance to win one of 10 $50 VISA gift cards. There is no purchase necessary. All entries must be received by 3pm Pacific Standard Time on February 10, 2012. and winners will be selected randomly. Be sure to check out the full official rules.