Can you help me with the trade in of my two brooks revel three please? What is the process! Do I send pics of the shoes and according to that I will be given a gift card to use? Please advise me more 

@Rima You can go here:

and select which model of revel 3 you have. Depending on the model, it looks like Rei values them between $9 and $18. REI will give you a prepaid shipping label, which will be subtracted from the value of the shoes, so you can expect to get ~$10 for your shoes.
Hope this helps. 

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