This bidirectional inflatable spiral valve is sometimes referred to as a "valve" and is mainly used in small boats and air cushions, but it is also used in some swimming pools. It is screwed into a hole with a diameter of 2 centimeters. Material: Plastic. Target audience: Adults. Product category: Valves. Type: Inflatable mattress, inflatable boat, inflatable sofa. Color: Black. Inflation pump type: External inflation pump. Sports and outdoor activities: Picnics, barbecues, camping. Please note: We recommend that you measure the holes before placing an order to ensure that their dimensions and parts are correct. Air cushion safety information: Warning. Not suitable for children under 3 years old. Warning: Can only be used in water within the depth range of children and under adult supervision.