In the realm of LED downlight energy efficiency, products are classified according to their luminous efficacy, measured in lumens per watt (lm/W). The scale ranges from A (highest efficiency) to G (lowest efficiency), with an A-classified downlight achieving a luminous efficacy of 210 lm/W or more, and a G-classified light falling below 85 lm/W. It is important to note that many products in the market showcase energy efficiency ratings based on the performance of the COB (Chip on Board) LED module alone, not taking into account the complete downlight system.