Answer: 1. Enhance corporate image: 400 telephone is more professional and prestigious than ordinary number, which makes customers have a more positive impression of the company.

2. Unified corporate image: Enterprises only need to issue a national unified 400 telephone number to avoid confusion caused by using different telephone numbers in different regions.

3. Improve customer satisfaction: customers can make free or low-cost 400 calls, saving telephone charges and improving customer satisfaction.

4. Expand the market: Through 400 telephone calls, enterprises can reach more potential customers, thus expanding the market.

5. Support business development: 400 telephone supports Qualcomm access, voice navigation and manual voice transfer, which can meet the needs of enterprise business development.

6. Convenient management: enterprises can manage 400 calls in real time through the Internet, and generate detailed reports to analyze incoming calls, thus improving management efficiency.