Using this holder is a breeze. First, check if the item you want to attach fits within the 50mm x 80mm space. Then, take the yellow plastic lock and attach it to the bottom of the holder. Place the holder on the DIN rail and position it as you wish. Once you're happy with the position, snap the holder onto the rail. It'll be securely in place in no time. Remember, the DIN rail itself isn't included with the holder. As for maintenance, since the plastic casing is durable, you just need to keep it clean. If you notice any dirt or debris, you can wipe it off with a dry or slightly damp cloth. Avoid using harsh chemicals as they might damage the plastic. And if you want to modify it, you can easily machine, drill, or cut the plastic casing to fit your specific needs.