fig1 after insertion of the lower conduit box tab 76 the conduit box 78 is lowered and the box 78 is mounted on side of stud 22 with particular reference to fig1 and 14 there is shown a construction aid that can be used in conjunction with internal wall construction while the construction aid is shown with respect to mounting upon a masonry or concrete wall which often are not true so that if an internal wall is mounted in a conventional manner the wall will not be true or level with respect to the other wall the ceiling or the floor of the room construction aid comprises strip 80 having projections 82 84 that provide for receiving and retaining transverse member 86 having a relatively flat surface strip 80 is anchored to the underlying wall by anchoring means 87 88 shims not shown can be used at the anchoring means to provide a surface of member 86 that will enable the internal wall mounted thereupon to be true thereby enabling the internal wall to be in the proper geometric relationship with particular reference to fig1 there is shown a fragmentary plan view of a metallic plate 88 such as 16 gage galvanized steel in which a series of locking slots 30 a k and 32 a k are cut the slots are described in detail above with particular reference fig3 a spacing u201c d 1 u201d is shown the.