Which entry would provide details on the materials used in a closet?

The choice that provides details on the materials used in a closet is the one that explicitly focuses on closets. The designation "CL" often refers to closet-related entries in data or reports. Therefore, both "CL 1" and "CL 2" are likely to contain specific information about closets. Of these, the chosen entry “CL 1” suggests it may be the primary or first listing related to closet materials, thus offering comprehensive insights into the types and specifications of materials utilized in the construction or design of a closet.

In the context of the other options, "Bedroom 1" and "BR 2" may deal more broadly with bedroom components, which could include elements like furniture or general fixtures, but not specifically focus on closet materials. Since these do not directly indicate a focus on closets, they would be less relevant for finding detailed information about materials specifically used in a cupboard or closet space.