The present invention described and shown in the specification and drawings provides novel recombinant DT-based immunotoxins, and, more specifically anti-T cell immunotoxin fusion proteins. The fluid may be a compressible or a noncompressible fluid. The first lock end is connected to the second lock end, thereby locking the first wristband portion and the second wristband portion together to surrounding a receiving space for receiving a user’s wrist. The detector of the invention provides a compact, relatively easy to use, directional neutron detector for use in locating and monitoring special nuclear materials and other sources of fast neutrons. Due to the parallel co-placement of the speaker and microphone in the single lateral assembly, the length of the device is substantially shorter than that of prior hearing aid devices. The illumination apparatus further includes a one or more electrical conductors coupled to the radiator, wherein the electrical conductors are adapted to couple electrically to the solid state light emitting source.