Is Findster Duo free of monthly fees? Jane Jonson Updated January 13, 2017 15:38 Follow Yes, Findster Duo is free of monthly fees and doesn’t requires cell coverage or SIM card. Related articles Does Findster Duo fit in my pet’s collar? Does Findster Duo include a warranty? In which countries can I use Findster Duo? Have more questions? Submit a Request Comments 0 comments Please sign in to leave a comment.