This open inflatable plug features a metal bypass tube through the center of the plug to pressurize plumbing lines by inducing air or water. The rigid bypass tube allows for a high volume of air or water to pass through the plug while still maintaining the versatility of an inflatable plug. Inflatable plugs are not as durable as mechanical plugs, but provide a versatile solution for out-of-round plumbing or hard-to-reach locations.

The standard 555BP version includes an L-shaped quick connect off the top of the plug for inducing air or water through pump baskets and other tight areas. This version has a simple tire valve attachment for inflating the plug.