2. Hinges and locks are active parts which should be tightened once they are found loose. When hinges make noise, lubricant should be replenished in time. When the lock turns uneasily, a proper amount of pencil lead power can be fed into the keyhole, but never inject oil casually. Try to keep the relative air humidity at 60%--75% when using the product. During the ground heating period, avoid leaving the uninstalled doors directly on the ground to prevent baking. Timber shrinks when dried and bulks when wetted, so, it is normal that slight crack or shrinkage occur due to great temperature and humidity differences. Never mind, for those phenomena will naturally disappear as the seasons change. To maintain the brightness and color of the door, waxing should be performed regularly.