The Stereognostic Bag (A181) is a drawstring bag used in primary sensorial work to support the development of stereognostic sense — the ability to perceive and identify objects through touch alone, without visual input. It is typically used with pairs of familiar objects or geometric solids, inviting children to match or identify contents by feel. This material is straightforward to introduce and highly engaging for children in the 3–6 environment, making it a reliable go-to for individual sensorial extensions.