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
D, North Wing, 4/F, Block2, Vision Shenzhen Business Park, No. 9 Gaoxin 9th South Road, Shenzhen Hi-tech Industrial Park, NanShan District, Shenzhen, China
