Sizing RC Network for Contactor

I want to put a RC network across both of the coils of two mechanically interlocked size one 120 vac contactors.

Can you help me size this network? Looking at different networks they can have varying resistance and capacitive values. The contactors in question change state a couple times a month if that matters at all.

Thanks in advance for your reply.
You might find the following websites useful:

William (Bill) L. Mostia, Jr. PE
ISA Fellow
Sr. Functional Safety Consultant
SIS-SILverstone, LLC.

"No trees were killed to send this message, but a large number of electrons were terribly inconvenienced." Neil deGrasse Tyson

Any information is provided on a Caveat Emptor basis.
Generally you do not need the snubbers to handle the inductive kick-back with ac coils. Only where solid state switching of DC coils, in which case diodes are typically used to protect the switching devices.