These PB613 kits are backlit LED switches with momentary DPDT action.
At Expat Audio, we use these on the Mic Pre Controllers.
The kit comes with a Red LED as standard, as well as two aftermarket LED's in Green and Yellow that can be fitted.
Datasheet available at: http://www.highlyusa.com/highly/pdf/PB613.pdf
Please note: Each Kit contains one single switch. 3 kits must be purchased to fit in a 3 button controller board.