If the ARC is order with the -D option that contains the 106 Adapter & Coupling and it is going to be used with an S106-205, RS42, or TS42 motor, then one more part will need to be ordered. For the S106-205 and RS42 motors, the RS42 ENC PLATE is needed. For the TS42 motors, the TS42 ENC PLATE is needed.
The -C option that contains the 83 Adapter & Coupling requires similar parts. For the RS34 motors, use the RS34 ENC PLATE. For the TS34 motors, use the TS34 ENC PLATE.