10 offers from $18.95. Acme Electric T181052 Buck-Boost Transformer, 1 Phase, 60 Hz, 0.75 kVA, 120 x 240V Input, 12/24V Output, Steel. 4.3 out of 5 stars. 12. 3 offers from $129.26. Acme Electric T279740S Low Voltage Distribution Transformer, Single Phase, 120/208/240/277 Primary Volts - 120/240 Secondary Volts, 1 kVA.