The products uses two-way slide to ensure reasonable force on rubber barrel and prolong its service life. Rubber barrel uses structure of "wire-capsule expansion packer rubber barrel ", using NBR rubber modified special technology with temperature resistance of 120  HNBR rubber barrel modified technology with temperature resistance of  150 FPM peroxide cross-linking technology with temperature resistance of  180 . Liner composed of high strength material (Si3N4) isused in tool's hole shrinkage position and sliding sleeve sealing position to raise anti-wear and operation reliability.