A plug for a tubular service entrance of a conduit, wherein the plug includes a core body having a central hollow channel extending from a first end to second end of the core body; at least one flexible fin extending radially outwardly from the core body and having an outer diameter greater than the inner diameter of the tubular service entrance so that the plug is adapted to fit tightly into the tubular service entrance, and wherein the at least one flexible fin is deformable to adapt to the shape of the service entrance and apply a lateral force against the inner diameter of the service entrance. A plug dispensing magazine for storing and dispensing service entrance plugs to be service entrances of a conduit prior to installation of a liner in the conduit and a method of sealing the service entrances.