New Gold Glass Design Filament Type Brilliant E27 ST64 Led Home Light Bulb 4W and 400Lm Brightness. Bulb type ST64, light color 2200k (Warm white) The bulb is capable of replacing the 35W old filament lamp. Filament diode With gentle electrolux. The energy efficiency of light bulbs is expressed in lm / W. There are currently a number of different bulbs with different efficiencies. Energy-efficient LED bulbs are on average 5 to 10 times more efficient than a filament lamp. Consequently, LED bulbs reduce energy consumption and costs by 50-90% compared to a standard lighting solution.