has a bore with an internal thread 194 an exterior thread 196 complementary to and for engagement with the threaded opening 190 and lock means such as keys 198 operable from a first position seen in fig6 a allowing rotation of the insert 192 into the threaded opening 190 and a second position seen in fig6 c locking the insert 188 against rotation in the threaded opening 190 first the proximal end 122 of the stud 118 is engaged with the internal thread 194 of the insert 188 until the keys 198 engage the first end surface 158 of the press member 148 a socket of a power tool is placed over the wrenching surface 146 so that a force can be selectively applied to rotationally move the press member driver 136 on the rotational axis 120 the rotational movement of the press drive member 136 drives the stud 118 the press member 148 and the insert 188 in mutual rotation on the rotational axis 120 such that the external thread 196 of the insert 188 is threaded into the threaded opening 190 of the parent material 192 the mutual rotation is obtained because the torque required to overcome the detent 165 is greater than the torque required to threadably engage the insert 188 into the parent material 192 as seen in fig6 b rotation of the insert 188 is stopped when the lower engagement surface 186 of the depth gage 176 contacts a surface 200 of the parent material 192 surrounding the threaded opening 190 the depth gage 176 therefore insures that the insert 188 is longitudinally located at a predetermined depth below the surface 200 of the parent material 192 rotation of the.