Declarations that meet the following conditions have legal effect: 1. Signed by the representatives of Party A and Party B and stamped with the official seal of the company; 2. The representatives of Party A and Party B shall sign and affix the special seal for corporate finance; Three. Signature of legal representatives of both parties. Legal effect refers to the binding force owned or endowed by law. Normative legal documents and non-normative legal documents have certain binding force, which requires people to act in the way stipulated in the legal documents. Article 470 of the Civil Code stipulates that the contents of a contract shall be agreed by the parties, and generally includes the following clauses: (1) the name and domicile of the parties; (2) Subject matter; (3) quantity; (4) quality; (5) Price or remuneration; (6) Time limit, place and method of performance; (7) Liability for breach of contract; (8) Methods for resolving disputes. The parties may conclude a contract by referring to the model texts of various contracts.