Find the Vibe model and serial number.

Option 1: From the hardware sticker located on the back of the board

Vibe V1 55" - Bottom right corner on the back of the board

Vibe S1 55" - Bottom middle on the back of the board

Vibe Pro 75" - 1. Board serial number left side 

                        2. OPS serial number right side

Option 2: From the device interface

Vibe V1 55" - 

Click on the up caret on the launch bar

Click on the Settings Gear icon

Scroll down to the General section

Click on About Vibe

Vibe S1 55" and Vibe Pro 75" -

Click Touch to Start

Click the up caret on the launch bar and touch the Settings Gear icon

Click About Chrome OS