Please note, the PV INVERTER type must connect the inverter as the A source, with the inverter and PV system serving as the main power. The stable grid power serves as the B source. The intended use is for photovoltaic to be the primary power source, with utility power as the backup. Dual power switch, PC level, no interruption. For PV system and inverter to city power only, not for city power and generator to city power and generator. Batch numbers may vary across different production batches; this does not affect product performance. Type: 63A. Color: white + black. Material: PC. Size: 107 x 96 x 76mm. Package contents: 1 x Automatic Transfer Switch. Only the above items are included; other products are not included. Note: Lighting and different displays may cause slight variations in the color of the item compared to the actual product. Measurement error allowance is +/- 1-3cm.