The 7002T is low-voltage (7002T-12 is 12VDC, 7002T-24 is 24VDC) and the 7004T is 120VAC. Other than that, they are the same alarm.
The 7002T is low-voltage (7002T-12 is 12VDC, 7002T-24 is 24VDC) and the 7004T is 120VAC. Other than that, they are the same alarm.