is available from bay state polymer distribution inc p o box 40055 bay village ohio 44140 other suitable materials include kraton pvc polyurethane and engage by using a transparent material the ear coupler can more easily and accurately be placed over the subject 39 s ear opaque materials can be used to create the desired acoustic environment but they do not allow the clinician to visualize the placement of the coupler over the center of the subject 39 s ear preferably the ear coupler is comprised of one piece which may result in lower manufacturing costs compared with multi piece couplers however the coupler can be composed of more than one piece so long as the pieces or their connections are flexible enough so that ear coupler can accommodate the irregular and curved shape of a subject 39 s head the ear coupler can be made by injection molding thermoforming and other processes the ear coupler is not u201c handed u201d meaning that it can fit on either the right or left ear the ear coupler is provided clean and can be sterilized as needed for certain applications the ear coupler is designed to be disposable the annular side wall 20 forms a ring.