These replaceable tissues offer unsurpassed realism in ultrasound imaging, even after repeated full catheterizations and needle insertions—there is no perceivable residual image of previous procedures. They are also ultra-durable and self-sealing tissues—capable of enduring hundreds of needle insertions and dozens of full catheterizations. The tissues includes the necessary landmarks that are both palpable externally and visible under ultrasound. Practice isolation and needle insertion on all three access sites using ultrasound guidance - increase skills and confidence in insertion depth, angle and location.