ASUS Chromebook 202SA Keyguard Communication Devices it might be the one

it might be the one shown here

US English version

but locks under all 4 edges of the front clip

You can optionallly choose to make an oversized perimeter with or without mounting holes you can use for fabricating your own attachment method

The keyboard is specifically designed to aid learning in young children

ASUS Chromebook 202SA Keyguard Communication Devices it might be the oneKeyguard for the ASUS Chromebook 202SA, US English version. The default material is 3 16" clear acrylic. 1 8" high impact PMMA is available for users who require the openings to be shallower, but is not recommended, since it is more flexible and may become warped or dislodged. There are also a number of 1 4" thick materials available. No attachment method is provided with this keyguard. You'll need to attach it yourself with something like double