The Fabric Box (A191) is a sensorial material containing fabric swatches for matching and grading work, supporting the refinement of the tactile sense in the 3–6 environment. Children use it to pair identical fabrics by texture and weight, typically while blindfolded or with eyes closed to isolate the tactile sense as Montessori intended. It's an essential part of a complete sensorial sequence and holds up well to daily handling when the swatches are properly maintained.