If you are looking for the official stock firmware for the Vivo Z1 PD1730C, you can download it here. The firmware is useful for fixing software related problems like.
- Boot loop
- Unbricking of device
- Un-rooting your phone
- Update firmware
- Restore to factory defaults
- Fix malware/monkey virus etc
Download Vivo Z1 PD1730C Stock Firmware
Download the stock firmware for your Vivo below. Flashing is via recovery mode/update.