Abstract: In accordance with an illustrative embodiment of the present invention, there is disclosed herein a device for anchoring downhole apparatus such as a safety valve in a tubing landing nipple, and a running tool for lowering the anchoring device at the end of a wire line into the tubing.The anchoring device comprises a body member that carries locking dogs which are shifted outwardly and engaged by the longitudinal movement of an expander mandrel. An expansible ring that is maintained on the mandrel by shear pins functions to lock the mandrel in the engaged position of the dogs. The running tool comprises a control sleeve having pivotally mounted connecting keys which remain engaged with the mandrel until the locking dogs are properly engaged and which then are released automatically from the mandrel. A safety shear pin makes it possible to free the running tool from the anchoring device in the event of incorrect anchoring of the latter and, when sheared, provides a "tell-tale" of incorrect installation.