CHANGZHOU ZCTEKINSTRUMENTS CO., LTD. Address: room 420, building 3, no.18 huashan road, xinbei district, changzhou city, jiangsu province After-sales operator: 0519-85120128 Maintenance after-sales service: 0519-85120128-8016 Technical support: 0519-85120128-8006 Fax: 0519-85120107-8017 Email: sales@zctek.com.cn