Qnap Power Supply Unit For SP-4BAY-PSU, Compatible products TS-439 Pro/439 Pro II/439 Pro II+/459 Pro/459 Pro+/410U/419U, Silver, Total power 250 W, Purpose server. The QNAP SP-4BAY-PSU is an internal power supply which is specifically designed to work accurately with TS-469L, TS-469 Pro, TS-470. It can provide an input capacity of 100-240V AC, 50-60HZ and an output capacity of 250 Watts.