An end clinometer the bottom end of which is shaped to match the wedge-guide pin on the drive wedge; hence the two can be fastened together with copper shear rivets. When a drive wedge is driven into a wooden plug in a borehole the copper rivets break; after the clinometer has been removed from the borehole, the relation of the bearing and inclination readings to the flat face of the projection on the bottom of the clinometer case can be used to orient and place the deflection wedge in a manner so as to direct the deflected hole to follow the desired course. Compare: plain clinometer; line clinometer.