Made of a specially formulated material duplicating the feel of human tissue. When placed over the chest port, the chest tissue flap provides a realistic practice of palpating and accessing with proper access of the port being confirmed by a blood withdrawal - just like the real thing! Maintains its integrity even after numerous needle insertions. Measures 11-1/2" x 8". This is a replacement chest tissue flap for Chester Chest" (SB18636U).