the enclosed drawings it should be noted that the figures are only for illustrating embodiments and shall not be considered to limit the scope of protection directional specifications shall be viewed only as directional specifications in the drawings by means of the invention different variants of lock functions can be created by combining two different types of components with each other the modular based design makes it very simple to do re constructions re assemblies of e g a tubular rack or relocation of accessories on this tubular rack two lock housings and two lock plates together create a locking device fig1 shows a lock housing according to one embodiment wherein the lock housing is a component shaped as a shell with an open side and a closed side in the form of a cover 5 on the cover there is an interface with a hole pattern that forms the same pattern as the pins 1 form on the lock plate in addition to this there are holes with threads 7 there are recesses 8 on all sides of the lock housing which are perpendicular to the cover 39 s surface 5 opposite sides of the lock housing always have the same dimensions of the recesses 8 on.