It seems like you're asking about "2D CFL bulbs," which typically refers to 2D Compact Fluorescent Light bulbs. These bulbs are a type of energy-efficient lighting solution, often designed in a compact and flat shape with a distinct "2D" appearance (like a "double D" or square/rectangular form). Here's a bit more detail:

• Energy Efficiency: CFL bulbs are known for using significantly less energy compared to incandescent bulbs, making them cost-effective in the long run.
• Shape: The "2D" in the name usually refers to their unique shape, which is flatter than standard spiral CFLs. They’re commonly used in ceiling fixtures and recessed lighting, where their shape allows them to fit well.
• Lifespan: CFLs generally last much longer than incandescent bulbs, reducing the frequency of replacements.