A dual-selective thermal emitter with enhanced subambient radiative cooling performance is introduced, which achieves selective emission in both atmospheric transparent windows (8–13 µm and 16–25 µm) and reflection in other wavebands. This design surpasses existing thermal emitters in subambient cooling capacity, reaching -9°C under strong sunlight, and exhibits high weather resistance and color compatibility. The emitter is based on a scalable polymer-metal structure, with high emittance in the two atmospheric windows (83.2% in 8–13 µm, 67.5% in 16–25 µm) and high reflectance in other wavebands. It demonstrates excellent durability, with performance maintained after 300 hours of UV exposure, 5 months of outdoor exposure, and 12 hours of water treatment. The emitter shows superior cooling performance compared to conventional materials, especially in arid climates, and maintains cooling efficiency even when colored. The design provides a practical and scalable solution for sustainable thermal management.A dual-selective thermal emitter with enhanced subambient radiative cooling performance is introduced, which achieves selective emission in both atmospheric transparent windows (8–13 µm and 16–25 µm) and reflection in other wavebands. This design surpasses existing thermal emitters in subambient cooling capacity, reaching -9°C under strong sunlight, and exhibits high weather resistance and color compatibility. The emitter is based on a scalable polymer-metal structure, with high emittance in the two atmospheric windows (83.2% in 8–13 µm, 67.5% in 16–25 µm) and high reflectance in other wavebands. It demonstrates excellent durability, with performance maintained after 300 hours of UV exposure, 5 months of outdoor exposure, and 12 hours of water treatment. The emitter shows superior cooling performance compared to conventional materials, especially in arid climates, and maintains cooling efficiency even when colored. The design provides a practical and scalable solution for sustainable thermal management.