Hold downs or tie downs in construction and structural engineering refers to the use of steel devices or other hardware attached to plywood sheer wall planks. Use of these tie downs helps prevent violent uplift by providing resistance when in plane lateral loads are applied at the top of the wall. Clamping devices used to hold items within steel structures or concrete flooring, such as pipes, in place during construction are also commonly referred to as hold downs. This type of use allows for movement along an axis for the pipe as needed during construction. The hold down is attached or connected to concrete flooring or structural slabs by use of epoxy and embedded anchor bolts while at the top wood posts would be holding it with screws, nails and bolts.