Sony S1 Service Driver (also known as the S1 Boot Fastboot Driver
Always ensure the device has at least 50% charge before starting, as a power failure during a flash can damage the main board. If you're looking for a specific download link step-by-step guide , could you let me know: What is the exact model of your Sony device (e.g., Xperia Z5, Xperia S)? sony s1 service flash file verified