The DOH is a high performance packer with double packer-off assembly which designed for open hole  application. The DOH is a part of the “SMF” multi-stage stimulation system, and provides secure, reliable, high pressure annular isolation during formation treatments. The unique modular design allowsone or more packers to be stacked within a given zone at the operator’s discretion to achieve multi-redundant independent annular isolation seals. The extremely compact design provides easy to handing and rig floor, liner string flexibility and trouble free deployment into even the most difficult well profiles. The DOH is set by applying pressure to the tubing string and  high performance is fully retained packing element reliably and holds extreme differential pressures from above and below through multi pressure and direction cycles.

Alternatematerials and configurations are available for severe environments and higher differential pressure ratings, a full line of accessory equipment is available providing a complete open hole multi-stage stimulation system.

Features：

• Doublepacker-off elements make more reliable isolation.

• All setting motions are locked by a ratchet locking system.

• Setting without rotation or reciprocation.

• Large bore diameter through the entire tool.

• Availability  various metals  and non-metals material meet to specific down-hole conditions.