Undead Controlling armor: Will Save or not Will Save

[emacleric]

Hello everybody!
I have a question: if I use the magic effects of an Undead Controlling armor, have undead targets to make a Will save to don't be controlled (like Control Undead spell)? Or are they automatically controlled since I activate the magic effect?
Thank you

[Kayerloth]

Is this a custom magic item? If so your GM decides and most likely it'll depend on which spell it is most similar to. Very likely intelligent Undead get saving throws at minimum.