Customer ordered 55 series rim NL-OP would they still need: 050105 55CK-NL ConversionKit?

If the 55NLOP was ordered form the factory, then it should have come with the NL Cams in the center case of the device necessary for a cylinder to retract the latch.
The cylinder would be mounted to the door using either a 110MD (for metal door) or 110WD (for wood door) assembly.
 
If the 55 Rim Center case they have does not have the cams necessary for NL operation, then part 050105-00 55 CK-NL kit would be necessary to add them.

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