I always heard of the T2 chip.
Those were binned Apple A series chips.
They used some of parts of it like the secure enclave, SSD controller, biometrics and hardware disk encryption.
Now days, those components are all already built into the M series chips.
T2 is no longer a thing since the Apple Silicon chips. Apple moved their support chips into the main SoC.
Those don't exist in ARM Macs.
Those were binned Apple A series chips.
They used some of parts of it like the secure enclave, SSD controller, biometrics and hardware disk encryption.
Now days, those components are all already built into the M series chips.