Kingbright 2520 Subminiature LED Indicators. The 2520 PCB LED indicators, from Kingbright, are available in single and quad block packages. They consist of subminiature LEDs within a black plastic housing. The housing holds the LEDs in place, at a right angle to the board.. Features of the 2520 PCB LED indicators: Subminiature LEDs Variety of colours Through-hole mounting Black plastic housing, right angle High-contrast UL 94 V-0 rated Diffused lens