Nonrotating stabilizer is a special tool in drilling to avoid blade wear and wall damage. The non-rotating stabilizerconsists of mandrel, copper washer, rubber sleeve, spacer sleeve and self-locking lower sub.During drilling, the nonrotating stabilizer transfer the torque by means of mandrel, the rubber sleeve is sliding and moving relativeto the mandrel, the rubber sleeve thus plays a role in stabilizer of well. A locking clutch(selflocking lower sub) will avoid sleeve rotation during wash over operation.