A trust may refer to a written statement or list to dispose of items of tangible personal property not otherwise specifically disposed of by the trust, other than money, evidences of indebtedness, documents of title, and securities, and property used in trade or business. To be admissible under this section as evidence of the intended disposition, the writing must have an indication of the date of the writing or signing and, in the absence of such indication of date, be the only such writing or contain no inconsistency with any other like writing or permit determination of such date of writing or signing from the contents of such writing, from extrinsic circumstances, or from any other evidence, must either be in the handwriting of the settlor or be signed by him or her, and must describe the items and the beneficiaries or recipients with reasonable certainty. The writing may be referred to as one to be in existence at the time of the settlor’s death; it may be prepared before or after the execution of the trust; it may be altered by the settlor after its preparation; and it may be a writing which has no significance apart from its effect upon the disposition made by the trust.