Where can I buy a SteriPEN Protector? Tim Archambault November 08, 2016 11:14 Updated Follow can't find online. Related articles What is the difference between the AdventurerOpti and the Protector? So, you're really upset with technical support. What is the difference between Defender, Classic, Traveler & Emergency SteriPENs? Comments 0 comments Please sign in to leave a comment.