N jack (female pin) Bulkhead suit RG213, LMR400.  AMPHENOL,

Silver Plated: Some slight tarnishing

RFShop Part Number: AMPH-NJ-213-BH
Amphenol Part Number: G825373S

These connectors are meant for RG213 but will fit  LMR400 and equivalent multi-strand cable too. Crimping is OK too. The wire on the solid inner LMR400 type is slightly too big for the hole on the centre pin. There’s a couple of ways to thin it down.1) Put a vertical saw cut in the inner wire then squeeze it tight with pliers. 2) Use a 0.075″ crimp to squeeze the cable inner to the right size.
Solder the pin on with both options.