Lag shield anchors allow lag screws to be installed into concrete and masonry walls. After drilling a hole into the material, lag shields should be tapped into place ribbed side first until flush with the surface. The lag screw can then be installed with a wrench or socket tool. The sides of the lag shield push out against the inside of the hole once the lag screw is installed, thereby locking it in place. The torque guidelines can be affected by the receiver material composition, freeze conditions over time, or sudden impact loads exceeding normal testing parameters.