The 5221629-5: It is a free-hanging, cap-style connector, meaning it terminates the cable end and includes a protective cap that stays on until the connector is mated.
Sourcing Reality — Obsolete, Quoted to Order
The 5221629-5 is officially listed as Obsolete.
Termination and Field Use
The 5221629-5 is a crimp-type BNC plug — the centre pin crimps onto the coax centre conductor, and the ferrule (not included) crimps over the braid and jacket. The free-hanging cap design means it is intended for cable-end termination, not panel mounting. The protective cap keeps the centre contact and dielectric clean during installation and storage — caps stay on till you mate. Standard BNC crimp tools for RG-59 or RG-6 cable sizes work, but confirm the specific cable diameter against the ferrule range before committing.