What do the numbers 3528 and 5050 mean?

[worldinfo12345]

Please let me know what is meaning of 3528 & 5050 in led lights commercial or home uses.

 

[Richard Burns]

This is the physical size of the LED chips used in the lamp 35 28 is 3.5mm by 2.8mm and 50 50 is 5mm by 5mm.
Generally the 5050 are considered better as there is a larger surface area for light output, but it does depend on the chip manufacturer and the lamp design.

 

[Brightspark2]

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