On this page, you will find the official link to download Lenovo Z1 Stock Firmware ROM (flash file) on your Computer. Firmware comes in a zip package, which contains Flash File, Flash Tool, Driver and How-to Manual.
Download Lenovo Z1 Stock Firmware (flash file)
File Name: Lenovo_Z1_CN_OPEN_USER_Q4275709.1_L_ZUI_0.9.084_ST_150729.zip
File Size: 920 MB
How to Flash: Follow Tutorial