Replying to Shop sent me free bindings

Randomly got an email that said my bindings have shipped but I didn't order bindings... tracking number says a pair of salomon guardians are gonna be at my door tomorrow. I didnt place an order, I have an account with the retailer but they dont have a credit card on file, and I have not been charged for the bindings on any of my cards. I need a new pair of bindings anyways so what should I do? Keep them and mount them up or let the retailer know they messed up?