Note: These replacement bands only for FITVII Slim Fitness Tracker, not for FITVII 1.57" Fitness Tracker.How to remove/resize the links: 1. Insert the tool needle into band side with indented hole.(Needles can be broken easly if you insert it into the wrong size)There's an extra needle inside the base of the tool. 2. Keep holding the band in place with your thumb,and gently turn the knob clockwise to push out the pin. 3. Remove or add links to make the band fit your wrist, put the pins back to the slot then knock it on the floor to connect the links. NOTE: Be sure the pin is not blocked by the slot edge on the tool and the needle stays in the hole. After-sale Service : Log in your Amazon account > Choose Your orders > Find the order ID > Click Contact seller