Using this viola case is simple. Just unzip it with the reliable YKK zippers, place your 15 - 15.5 - inch viola gently in the Contour Molded Plush - Lined Nest. You can carry it using the backpack straps for hands - free movement or the comfortable shoulder strap. The exterior pocket is great for storing small items like rosin or sheet music. When it comes to maintenance, keep it clean by wiping it with a soft cloth. Avoid exposing it to extreme temperatures or sharp objects that could damage the EPS polyfoam or the zippers. Also, make sure to close the zippers properly after each use to protect your viola.