A visit — yours or an inspector's — is the surest check on a new supplier. Send a date and what you want to see; the request reaches them as an enquiry you can track.
Address
A2026, Block 6, Hanyu Qisheng Square, No. 1666 of Xinluo Street Jinan District of China(Shandong) Free Trade Test Zone, Jinan, Shandong, China