A safety needle is provided which includes blocking structure to maintain a sharp tip of a needle safely within a housing and prevent re-advancement of a needle from a safety needle housing. The cell array includes a device isolation layer and active regions. A lance is formed within the terminal receiving chamber, and two projections are formed integrally on the lance, and project in a direction of a width of the terminal receiving chamber which direction is perpendicular to a direction of insertion of the terminal, and the two projections can be brought into sliding contact with apexes of the resilient curl portions, respectively. The device may be incorporated with non-elastic means, magnetic means, a tube holder, inner tube ,outer tube, conductive bus means, sensor means, and integrated circuitry to add a lot of desired features.