Drop-In anchors are female concrete anchors designed for anchoring into concrete. Drop the anchor into the predrilled hole in the concrete. Using a setting tool expands the anchor within the hole in the concrete. RKGD Drop-In anchors should only be used in solid concrete. Their main use is to insert threaded rod to suspend electrical cable trays, HVAC duct work and fire sprinkler pipe and heads. They can be used in applications that require a flush mounted anchor and when a bolt needs to be inserted and removed. A setting tool is required to set the anchor in the concrete.