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
Zhenghua Industry Park, No. 5 Wayao 4 Road, Wulian Community, Longgang Street, Longgang Dist, Shenzhen City, Guangdong Province, Shenzhen, Guangdong, China