This is a means of protecting an interest in an unregistered estate affecting land. A caution can protect a wide variety of interests, for example, rentcharges and franchises. For each caution there is a ‘caution title’ – a record, under a distinguishing number, of the details of the caution and of the declaration in support and of a plan showing the extent of the land affected by the caution. A caution is not an actual registration of any estate in land. It is merely a means to trigger notification to the person who lodged the caution when an application for first registration is made. There can be more than one caution in respect of the same property.