This is Lego part #3795 2x6 plate in Trans-Light Blue
NOTE: This part has two variations in color, but they are both listed as Trans-Light Blue on the original factory label
This part in this color is considered a Non-Production Part or Q Element. This means that it is an official Lego part that never appeared in this color in a regular set. These elements are often produced for Master Builder models so that large scale models can have a broad color palette.
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