The 031-70555-12G: This is not a generic 50 Ohm BNC; the 75 Ohm impedance is built into the dielectric and center conductor geometry, so mating it with a 50 Ohm system will cause a return-loss mismatch. The connector is rated to 12 GHz, which puts it well beyond standard SDI rates (3 GHz) and into the 12G-SDI range, meaning it handles UHD/4K video links without signal droop at the connector interface.
Kit Contents — Connector, Contact, Ferrule
The contact and ferrule are specific to Canare L-3.3CUHD — the ferrule inner diameter matches the cable jacket OD, and the contact barrel is sized for the center conductor. If you are terminating a different cable, the crimp dimensions will not seat correctly. The kit format simplifies field termination: one order code gets you everything except the cable and the crimp die.
Bayonet Lock, Free-Hanging Mount, 500 Cycles
Fastening is standard BNC bayonet lock — quarter-turn mate, positive detent. The connector is free-hanging (in-line), not panel-mount, so it terminates the cable end and mates with a bulkhead jack or another in-line adapter. The brass body with nickel finish gives reasonable corrosion resistance for indoor broadcast racks and field camera cable assemblies. Operating temperature range is -30°C to 85°C, covering outdoor broadcast vans and unheated equipment rooms.
Termination: Crimp Shield, Crimp Center
The shield termination is a crimp ferrule that compresses over the braid; the center contact crimps onto the center conductor. For Canare L-3.3CUHD, the recommended crimp die for the hex crimp tool is typically a 0.178-inch hex for the center pin and a 0.255-inch hex for the ferrule (verify with your tool manufacturer's die chart).