What type of anchor is considered a female type fastener?

A female type fastener is one that has an internal thread designed to accept a male threaded bolt or screw. The drop-in anchor and the single expansion anchor both qualify as female fasteners because they provide internal threads that allow a bolt or screw to be inserted for fastening purposes.

The drop-in anchor is specifically designed for use in concrete. It is inserted into a pre-drilled hole and provides a strong hold when properly installed. When a screw or bolt is inserted, it engages with the internal threading of the anchor, securing it in place.

Similarly, the single expansion anchor, which is typically used in various materials including concrete and masonry, also features internal threads to accommodate a screw or bolt. When the screw is inserted, it causes the anchor to expand, gripping the surrounding material firmly.

Both these anchors are designed to work together with male threaded fasteners, highlighting their function as female type fasteners. This differentiates them from other types of anchors that may not have the same internal threading capability or may serve different purposes.