KX-155A PN 069-01032-0101 and 069-01032-0201 with serial numbers between 29161 and 29321 have Mod 13 already installed therefore include the most current Liquid Crystal Display instead of the original Gas Discharge Display. It should be noted that the Mod 13 may or may not be marked on the PN label on the unit, however that serial number range was manufactured with the LCD.

For the KX-165A, Mod 4 incorporates the LCD upgrade. The applicability for the for the modification reads as follows from the Honeywell service bulletin:

'...applicable to the KX-165A P/N 069-01033-0101 with S/N 5101 and below, without Mod 4 installed...P/N 069-01033-0201 S/N 12941 and below without Mod 4 installed...NOTE: P/N 069-01033-0101 with SNs between 4491 and 5101 have Mod 4 identified on on the mod section of the SN label. P/N 069-01033-0201 with SNs between 12671 and 12941 have Mod 4 identified on the mod section of the SN tag. On these units, the Mod is fully included but the P/N label on some sub-assemblies is incorrect.'

View the LCD display on a KX-165A at https://youtu.be/oxerbdqWCi0.