Tenga Flip ZeroMale Masturbator, Using the finest materials yet and the latest technology. A seamless insertion point provides the perfect seal for no lubricant leakage and a strong vacuum made possible by a one-way valve. The FLIP 0 (ZERO) features TENGA's most intricate internal details yet for great sensation, and TENGA's pioneering FLIP-open function keeps the item hygienic for multiple uses.