the present invention , and inventive system , describes a lock system that is designed to be attached to an existing cast iron loose grate and or manhole covers that sits in a cast iron or other material frame allowing the loose grate to be locked into the frame so it cannot be removed from the frame accidently or on purpose without the proper tool to unlock the security locking bolt . in some embodiments of the present invention , the present invention does not need a frame and interacts with the wall holding the cover directly . in at least one embodiment the present invention operates by an upper and lower section . the lower section may have multiple bars that operate independently of each other . these lower sections can rotate about a screw which is located in a hole drilled through a grate or manhole , such that the lower sections can rotate across the manhole cover and extrude past the radius of the manhole cover .