Those are wire connectors, usually used on low voltage wiring like telephone or doorbell. Hard to tell from photo what kind of wire that is. Maybe part of a security system?

Thank you! Super helpful.

Thank you, Dennis! I just added a better photo. There seem to be 2 sets of wires. One set are as you said red-black-yellow and one set of 4 red-black-yellow-blue. Do you think that we could connect a bell to these wires? This house has no bell and we'd like to connect a hardwired one for the simplisafe video bell. Thank you so much.

Can you figure out where those wires go?

One set goes into another closet with a defunct old ADT system, and one goes into the soffit.

"Do you think that we could connect a bell to these wires? This house has no bell and we'd like to connect a hardwired one for the simplisafe video bell."

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