They make TIRs that can have a beam divergence as little as 4deg. emitter dependent which is also achieved with reflectors. The difference with TIRs is that what we call spill light is captured and sent forward. The TIR can control the angle of the emitted light. I’m not 100% sure as to what is “special” about Elzetta’s optics; I believe you can drop in optics from manufacturers that make TIRs with the standard standoffs?