Drop in anchors are internally threaded concrete anchors that are usually mounted on the top and flush with the concrete surface. These anchors are usually used to support handrails, lighting fixtures, pipes, etc. They are best suited for light to heavy duty stationary applications. Concrete-drop in anchors are available in 1/4", 3/8", 1/2", 5/8" and 3/4" diameters and are available in standard zinc, 304 stainless steel and 316 stainless steel to meet many construction needs. After installation, the fixture is detachable because the drop in anchor can remain in the concrete, but the threaded rod or bolt used can be unscrewed and removed.