Obsolete — what crosses when it's dry?
The TE Connectivity 221185-9 is listed as Obsolete in the lifecycle record. That means the factory no longer builds it, and the franchise channel is dry. The bayonet lock gives quick quarter-turn mating, rated for 500 cycles. For a replacement, TE does not list an official successor under this base number; your best bet is a parametric search for a 75 Ohm BNC crimp plug with the same cable group and termination style, sourced against your BOM quantity.
The cable group is RG-59, the most common 75 Ohm coax for analog video and CCTV runs. The 500-cycle bayonet lock is typical for patch panels and field-test leads where the connector sees regular reconnects.
RF performance — 75 Ohm at 2 GHz
Rated impedance is 75 Ohm, with a maximum frequency of 2 GHz and insertion loss of 0.15 dB. The 75 Ohm characteristic suits video baseband and digital broadcast signals where the cable plant is already 75 Ohm — think SDI, composite video, or RF distribution up to 2 GHz. The dielectric is polyethylene, which is standard for this class.