MATERIAL: Made of rubber with excellent expansion and recovery. Recommended inflation for daily use: 30 PSI. SIZE: The diameter of the rubber plug is 1.75 inches in the non-inflated state. The maximum diameter expands to 2.25 inches when 40 PSI air pressure is applied. PRODUCT DESIGN: The copper valve core allows for easy release of air when deflation is needed. Deflation is convenient and quick. The 2.34 inch ring diameter helps prevent the rubber plug from falling into the pipe when deflated. EASY AND CONVENIENT TO USE: Insert the inflatable plug into the drain pipe and slowly inflate using a standard bicycle pump. Once inflated, proceed with water testing. After testing, deflate the plug and remove it easily. APPLICABLE SCENARIOS: Suitable for use with shower drains, floor drains, bathtub pipes, bathroom pipes, toilet tees, swimming pool pipes, underground drains, and sewage pipes. COLOR: As shown MATERIAL: Rubber Note: Due to different production batches, there may be slight variations in product appearance and printed text, which do not affect functionality. PACKAGE CONTENTS: 1 x 2-inch Rubber Test Ball Pipe Plug. Other items not included. Note: Lighting and display differences may cause slight color variations between the image and the actual item. Measurement error allowance: +/- 1-3 cm.