Master Tool #4The Master Tool #4 Triple Ripple is a large butt plug from the Doc Johnson collection. The black butt plug has a small top and a ribbed shaft with three large ribs. The butt plug has a firm core with a soft and smooth outer layer for maximum comfort during insertion. The wide, flat base makes sure the plug is not inserted too deep. The wide base also makes the plug suitable to wear in combination with a strap-on harness.