A wiper plug typically has an elastomeric body mounted on a mandrel and elastomeric external fins that bear against the inner wall of the casing. The fins wipe mud solids and other accumulated debris off the inner wall of the casing.

The effectiveness of a wiper plug relies on at least one fin creating a seal against the surrounding casing or liner, and the body sealing against the mandrel. The elastomer material usually has a hardness that provides for structural robustness, such as for wiping of the casing or liner, and resistance to abrasion, yet is sufficiently malleable to be deformed so as to provide the necessary seals. However, the hardness decreases with increasing temperature, and thus at elevated temperatures within wellbores, the elastomeric body and the fins become susceptible to extrusion, which compromises their sealing capability. Therefore, an excellent wiper plug design is very important.

With plug designs mostly built from NBR/HNBR and aluminum, JST wiper plug are tested and qualified by many famous companies. The price is competitive and its performance is very well.