http://pastport.jp/user/grentechgroup ja-JP Founded in 1999, GrenTech is a high-tech enterprise specializing in the R&D and production of wireless communication systems，RF products and optical transceiver products. 2022-08-30T13:02:40+0900 http://pastport.jp/user/grentechgroup/timeline/Shenzhen%20Grentech%20Science%20and%20Technology%20co.%EF%BC%8CLTD%20%20%28GrenTech%29 grentechgroup http://pastport.jp/user/grentechgroup/timeline/Shenzhen%20Grentech%20Science%20and%20Technology%20co.%EF%BC%8CLTD%20%20%28GrenTech%29