Nothing carbon based lasts very long, and will have adsorbed plenty of odor hanging on the rack at the store anyway. Don't fall for the hype, you can't "reactivate" carbon at home in a dryer, that's ablatant lie and scientifically impossible. Nearly all of the sprays are peroxide/baking soda based and work well, I spray mine down straight out of the wash and allow them to air dry outside in my woods, and that works as well as anything is likely to.