Feature: 1. Reasonable Structure: One way valve help block the of contaminants, prevent the user from contaminants during cardiopulmonary resuscitation training. 2. Match To Use: The one way valve needs to be used with face shield, easy to install. Designed to be easy to use, if you live alone, you can use it in urgent condition. 3. One Way Valve Set: 20pcs of resuscitator one way valve are available, enough to meet your use and replacement needs, simple and practical, applicable for training. 4. Multiple Applicable Scenarios: Light weight and in small size, easy to store and carry, can be easily put into your bag, perfect for home, hospital, travel, etc. 5. Plastic Material: Important cardiopulmonary resuscitation accessory, resuscitator valve adopts excellent plastic material, safe and eco friendly, firm and sturdy. Specification: Item Type: One Way Valve Material: Plastic Height: Approx. 4.1cm 1.6in How to Use: Usedirectly. Package List: 20 x One Way ValveMULTIPLE APPLICABLE SCENARIOS: Light weight and in small size, easy to store and carry, can be easily put into your bag, perfect for home, hospital, travel, etc. PLASTIC MATERIAL: Important cardiopulmonary resuscitation accessory, resuscitator valve adopts excellent plastic material, safe and eco friendly, firm and sturdy. MATCH TO USE: The one way valve needs to be used with face shield, easy to install. Designed to be easy to use, if you live alone, you can use it in urgent condition. REASONABLE STRUCTURE: One way valve help block the of contaminants, prevent the user from contaminants during cardiopulmonary resuscitation training. ONE WAY VALVE SET: 20pcs of resuscitator one way valve are available, enough to meet your use and replacement needs, simple and practical, applicable for training.