Download Android 5.1 stock firmware for No.1 D5+ Smartwatch W612 version from here or here. Download Android 5.1 stock firmware for No.1 D5+ Smartwatch W613 version from here or here. Download Drivers & Tools and Root Pack v5 from here, here or here.
Archive name: No.1 D5+ (W612) / No.1 D5+ (W613)
Archive size: 1 GB / 353 MB
Image name: w612_D5+_160915, w612_D5+_161124, w612_D5+_161226 / w613_D5+_161229
Android version: 5.1 stock
Platform: Mediatek MT6580
Project: w612_wgl / w613_wgl
APDB: MT6580_S01_L1.MP6_W15.28, APDB_MT6580_S01_L1.MP6_W15.28_ENUM
Drivers & Tools and Root Pack details
Archive name: Drivers & Tools and Root Pack v5 04-10-16 / All Devices Core Tools and Root Pack v5 04-10-16
Archive size: 152 MB
Archive content: USB VCOM drivers, universaladbdriver_v3.0, SP_Flash_Tool_v5.16.36, QtADB, MTK Toolbox modded 64bit, MTK Toolbox 2.5.3d, UPDATE-SuperSU-v2.46.zip, NO.1 phone firmware update steps
Caution: Please do not update firmware unless you know what you are doing, you really want it or it is absolutely necessary. Firmware updates may occasionally have bad results, like bricking your device, temporarily or permanently. The firmware update process is done entirely at your own risk. Before attempting to update the firmware, back up your data.