Rated for 50 Ohm systems, it uses a PTFE dielectric and silver-plated centre contacts to keep the signal path clean through the junction. The nickel-plated brass body and dual bayonet locks give it the standard BNC quick-twist feel; it hangs free on the cable, no panel mount required.
The 50 Ohm impedance matches standard 50 Ohm BNC cable runs — the T splits the signal without an impedance bump at the junction. Silver-plated centre contacts hold up to repeated mating better than tin; the PTFE dielectric keeps the dielectric constant stable across temperature, so the 50 Ohm line holds from DC up through the BNC band.